







Terminologie mathematique 
20101031 

Adil pose la question : Bonjour ,
Pourriezvous m'indiquer les titre et auteur d'un bon dictionnaire
francais anglais de terminologie mathematique ?
Auriezvous egalement l'adresse d'un site web traduisant du francais
a l'anglais les termes ert expressions mathematiques ?
Merci par avance,
Adil PierreLouis Gagnon lui répond. 





J'ai l'équation X^n=Y Je cherche à sortir n. 
20081105 

JeanPhilippe pose la question : Bonjour.
J'ai l'équation X^n=Y
Je cherche à sortir n.
Existetil une équation donnant n=f(X,Y) ? PierreLouis Gagnon et Émile Létourneau lui répond. 





Logarithmique et semi logarithmique 
20080308 

azaar pose la question : Je veux savoir comment passer d'un échelle linière à l'échelle logarithmique ou semi logarithmique ? LierreLouis Gagnon lui répond. 





Dérivée logarithmique 
20070304 

Albert pose la question : Déterminer la dérivée première des fonctions logarithmiques suivantes : 1) f (x) = x exposant x 2) f (x) = x exposant e exposant 2x Claude Tardif lui répond. 





logarithme 
20061024 

Julie pose la question : Loga(x^24)  loga(x2) Claude Tardif lui répond. 





ln(x+3)+ln(x+2)=ln(x+11) 
19991124 

Thibault Portevin pose la question : "Résolvez l'équation : ln(x+3)+ln(x+2)=ln(x+11)" Je suis bloqué, pourriezvous m'aider? Claude Tardif lui répond. 





logarithme neperien 
19991110 

Louise Kieffer pose la question : D'où provient la valeur e ( 2,7....) des logarithmes népériens ? Claude Tardif lui répond. 





An analytic proof that a quadrilateral is a parallelogram 
20201026 

Apollo pose la question : Prove analytically that if ABCD is a parallelogram in which points P and Q trisects the diagonal AC, then BPDQ is a parallelogram. Penny Nom lui répond. 





An exterior angle of a parallelogram 
20191129 

A student pose la question : one angle of a parallelogram is four times the measure of the exterior angle adjacent to it. find the interior angles Penny Nom lui répond. 





A four person race 
20191119 

Juvy pose la question : Ben finished seven seconds ahead of Mike.
Noel finished three seconds behind of Sam.
Mike finished five seconds behind Noel.
In what order did the friends finish the race? Penny Nom lui répond. 





A problem with logarithms 
20190823 

Iriogbe pose la question : Find the value : if log3 (a6) =2b and log2 (a7) =3b Penny Nom lui répond. 





Why Mean? 
20190508 

Jill pose la question : A group of teachers were trying to figure out why the”mean” is called mean  do you know?? Penny Nom lui répond. 





4^x=2^x+6 
20190405 

Olivia pose la question : How do you find the (b,n) if the solution of the equation 4^x=2^x+6 can be expressed at logb(n) where b and n are both prime numbers? Penny Nom lui répond. 





Double the number of pennies each week 
20190228 

Donald pose la question : If I save a penny a week,double it every week,How many weeks will it take to reach 1,000,000 dollars Penny Nom lui répond. 





y=lnx+(1+ln2)/2 and y=x^2 
20190128 

Mike pose la question : Prove that y=lnx+(1+ln2)/2 and y=x^2 touch each other.
The course is about logarithm and root functions... how should I solve this problem? Penny Nom lui répond. 





Is a rectangle a parallelogram? 
20180228 

ellie pose la question : is a rectangle a parallelogram? Penny Nom lui répond. 





A parallelogram, a rhombus and a rectangle 
20180207 

Sambo pose la question : what do parallelogram, rhombus and rectangle have in common? Penny Nom lui répond. 





4444^4444 
20171210 

Sashi pose la question : 4444 to power of 4444=?
Please share the result with simplification. Penny Nom lui répond. 





The derivative of f(x)=2^x/x 
20171128 

Chhavi pose la question : f(x)=2^x/x.
Find f'(x). Penny Nom lui répond. 





Squares and rectangles 
20170715 

Tront pose la question : So, there's a general rule that all squares are rectangles but not all rectangles are squares. Im trying to find a term that would describe this relationship. I've found that if all of A is B but not all B is A then I'd say that A is a subset of B, but is there a term that describes the relationship as a whole? I don't want to describe the components, I want to describe the relationship as a whole. Penny Nom lui répond. 





3^2x5=27 
20161214 

danaja pose la question : solve for the following 3^2x5=27 Penny Nom lui répond. 





An open ball is an open set? 
20160623 

Aqeel pose la question : Theorem: The open ball is an open set? Harley Weston lui répond. 





The midpoints of the sides of a quadrilateral 
20160205 

Andrea pose la question : The segments, joining, in order the midpoints of consecutive sides of a quadrilateral form a parallelogram. Penny Nom lui répond. 





Consecutive angles of a parallelogram 
20160128 

Hanna pose la question : The consecutive angles of a parallelogram measures Penny Nom lui répond. 





Find two values of x satisfying f(x)=1 where f(x)=sin(ln(x)) 
20160121 

Ruth pose la question : I'm trying to find two values of x satisfying f(x)=1 where f(x)=sin(ln(x)) Penny Nom lui répond. 





Proof that an erroneous algebraic statement is false 
20151214 

Berteanu pose la question : I need help with this proposition:
"It exists x a real number that for every y real number 5*x2*y*y=1
This is false.
Let x be from R.
And I need an y real number that 5*x2*y*y!=1
Please,could you help me? Penny Nom lui répond. 





Parallelogram area 
20150804 

Nigel pose la question : To find the area of a parallelogram you multiply the base by the height of the parallogram, the height being determined by an imaginary line drawn at right angles to the base. However if I made a parallelogram with joints at each corner and maipulated it to an upright position where the base and sides were at 90 degrees to each other,, I could then simply multiply the base times the height to get the area. Since the sloping side of the parallelogram does not vary in my imaginary jointed model, why can I not simply multiply the base by the sloping side to get the area in the same way that I multiply the base times the height of a square to find its area ? I cannot find the answer to this on the internet although I have searched. Chris Fisher lui répond. 





Manipulating an expression using logarithms 
20150518 

Katie pose la question : Solve x=At^be^ct for b in terms of c.
The e is Euler's number, not a letter or random placeholder. v
I've tried 2 methods on my calculator, and I am unsure as to why they give me different answers, and which one is correct.
For some reason, when placing a multiplication sign in between the A and the first t, I get a completely different answer. Why is this?
Also, which is the right answer for the question I have?
Thank you!
Katie :) Penny Nom lui répond. 





A parallelogram inscribed in a circle 
20150204 

narendra pose la question : how can we prove that a circular parallelogram is a rectangle? Chris Fisher lui répond. 





logbase4 (sin x) = 0.5 
20141026 

Susan pose la question : Solve for x: logbase4 (sin x) = 0.5 Penny Nom lui répond. 





Interior angles in a parallelogram 
20140830 

xavier pose la question : so, one of my math homework questions requires me to know how to find out how to find the interior angles in a parallelogram, the question is, "how many interior angles does a parallelogram have?" Penny Nom lui répond. 





Logarithms 
20140828 

effaryna pose la question : how logarithms is applied in everyday life? Penny Nom lui répond. 





Differentiate ln[x(2x4)^1/2] 
20140628 

Igwe pose la question : If y=In[x(2x4)^1/2],find dy/dx at x=3 Penny Nom lui répond. 





How do we use logarithms in our daily life 
20140601 

ss pose la question : how do we use logarithms in our dailylife Penny Nom lui répond. 





The inverse of y = 5^x 
20140307 

Melody pose la question : how do you find the inverse of y = 5^x Penny Nom lui répond. 





The area of a parallelogram 
20131128 

shivam pose la question : a parallelogram has sides 34 cm and 20 cm .one of its diagonal is 42 cm. calculate its area Harley Weston lui répond. 





Evaluate log3 14 
20131117 

Tash pose la question : Use the Change of Base Formula and a calculator to evaluate the logarithm, correct to six decimal places. Use either natural or common logarithms.
log3 14 Penny Nom lui répond. 





n log n = 36 * 10 ^ 12 
20131112 

shihab pose la question : How to find value of n in this equation :
n log n = 36 * 10 ^ 12 Penny Nom lui répond. 





2^x . 5^3 = x^4 
20130905 

Zuhdina pose la question : Hi, I got a question, 2^x . 5^3 = x^4
I want to know the value of x without using calculator, I've already done some questions in logarithm and I always stuck in the same model equationI think if someone shows me the way, I can do the other 'stuck equations' Penny Nom lui répond. 





4=(1+.08)^x 
20130615 

Samantha pose la question : I can't seem to understand how to solve for x when it is in power form, here is the equation:
4=(1+.08)^x Penny Nom lui répond. 





How do i write log_8(P) =7 in exponential form? 
20130414 

nancy pose la question : How do i write this in exponential form log8P =7 Penny Nom lui répond. 





Solve 8 logx > x 
20130219 

Fulvio pose la question : Hi, could you solve this equation in algebraic form:
8logx>x Harley Weston lui répond. 





What is the domain of f(x)=sin(ln(x))/ln(x)? 
20130206 

Behrooz pose la question : Hi, the following problem may be interesting:
What is the domain of f(x)=sin(ln(x))/ln(x)?
Be careful, domain is not obvious.
Best regards
Behrooz Penny Nom lui répond. 





A question about a parallelogram 
20121014 

Renu pose la question : Question from renu, a parent:
ABCD is a parallelogram. BP and DQ are two parallel lines cutting AC at P and Q respectively. prove that BPDQ is a parallelogram Harley Weston lui répond. 





The exponential form of log8=P 
20120425 

Kristina pose la question : what is the exponential form of log8=P Penny Nom lui répond. 





How long will it take lee to catch up with jodie? 
20120321 

kirsten pose la question : for example, if jodie is on the bus travelling at 10 m.p.h and lee is walking at 4 m.p.h how long will it take lee to catch up with jodie?? what is this mathematical name for this Harley Weston lui répond. 





If a parallelogram is a cyclic quadrilateral then it is a rectangle 
20120201 

Kim pose la question : Show that if a parallelogram is a cyclic quadrilateral then it is a rectangle.
Hint: Observe that in a parallelogram ABCD we always have Triangle ABC is congruent to Triangle CDA. Robert Dawson and Chris Fisher lui répond. 





A problem in logic 
20120119 

Ghader pose la question : The puzzle below I know the answer to; because someone told me! My question is: how could I answer it using logic, maths, etc. what field of inquiry does this kind of problem fall into?
Puzzle: You are in a room with two men: one is a compulsive liar and the other is a compulsive honest. There are two doors: one leading to heaven, the other to hell. The two men know which door leads to where. You want to go to heaven but are allowed only ONE question from one or the other of the two men. What would that question be?
[The question to ask, from either man, is: "if I asked the OTHER man which door leads to heaven, which door would he point?". You would then choose the other door.]
Has this answer got any basis in logic or maths at all? Robert Dawson lui répond. 





A log equation in exponential form 
20111111 

Sarah pose la question : Express the equation in Exponential form
log2 to the 16th power=4 Penny Nom lui répond. 





Uses of logarithms 
20111109 

BEA pose la question : what is the use of logarithmic functions in real life or daily life? Penny Nom lui répond. 





Infinite Logarithmic Series 
20110808 

Sourik pose la question : Dear Expert,
In my Amithabha Mitra and Shambhunath Ganguly's "A Text Book of Mathematics" I found the formula of log (1+x) where the base is e and x lies in between 1 and +1.As I want to learn Mathematics,I am not satisfied with the mere statement of the formula.Please help giving me the full proof.
Thanking you,
Sourik Robert Dawson lui répond. 





Exponential form 
20110518 

Kara pose la question : How do I write this in exponential form?
log 1/8 = 3 Penny Nom lui répond. 





The rate of change of the area of a parallelogram 
20110405 

Gevork pose la question : Let a parallelogram have sides of 8 and 12 and let vertex angle A be decreasing at a rate of 2degrees per minute. Find the rate of change of the area of the parallelogram when angle A equals 30 degrees. Penny Nom lui répond. 





ln(12 x) = 6 
20110303 

Carolyn pose la question : solve the equation
ln12x = 6
Thank you
Carolyn Penny Nom lui répond. 





The diagonals of a parallelogram 
20110217 

ginger pose la question : Find the diagonals of parallelogram where the the side is 40 and the bottom side is 15. Penny Nom lui répond. 





Daily life example of logarithms 
20110204 

owais pose la question : what are the application or daily life example of logarithms? Harley Weston lui répond. 





Simplify the logarithmic expression 
20101202 

Adori pose la question : Use the properties of logarithms to simplify the logarithmic expression. Log(1/250) base 5 Penny Nom lui répond. 





A Taylor polynomial for (lnx)/x 
20100929 

Dave pose la question : I have a series problem that I cannot solve. The problem asks for you to compute a Taylor polynomial Tn(x) for f(x) = (lnx)/x. I calculated this poly out to T5(x) and attempted to use this to identify a pattern and create a series in order to calculate Tn(x). However, the coefficients on the numerator out to F5prime(x) are as follows: 1, 3, 11, 50, 274... Ok, so the negative is an easy fix > (1)^n1. But the other coefficients are stumping me. I can't see any sort of pattern there and I've tried every trick I know. Is there another way to go about this?
Thanks! Chris Fisher lui répond. 





An equation involving logarithms 
20100927 

mindy pose la question : Hi,
I am trying to find x, the equation is:
log_2(log x + 2 (log x)^(1/2) + 1)  2 log_4((log x)^(1/2) + 1) = 1
Thank you very much for your time. =) Harley Weston lui répond. 





A logarithmic equation 
20100908 

Rohit pose la question : x^2 + k*ln(x)  c  k = 0
Where k and c are constants. Penny Nom lui répond. 





Converting kilograms to cubic metres 
20100716 

Ilai pose la question : I want to convert kg to cubic metre Penny Nom lui répond. 





12 coins 
20100707 

Eden pose la question : We have 12 coins same in size and shape and also weight.
But among these, one coin which has same size and shape, but not in weight
and we can't know that this coin was lighter or heavier.
We must decide which coin was lighter or heavier among these 12 coins in
4 times of weighting with scale. Stephen La Rocque and Tyler Wood lui répond. 





y =  log(x) 
20100428 

Alex pose la question : y=  log(x), where y = 4.3
solve for x. Harley Weston lui répond. 





Pyramids and parallelograms 
20100401 

Vivi pose la question : Hi, my name is Vivi, and math teacher is giving a geometry test. I tend to forget how to find the surface area and volume of triangular pyramids and parallelograms. Do you have a way of remembering how to find the surface area? Harley Weston lui répond. 





Log[f(x)] 
20100308 

sourabh pose la question : What is the number of solutions of the equation
9 x 2  18 x + 5 = 0 for x, such that the expression
log10[(x+1)(x+2)] exists? Harley Weston lui répond. 





Growth rates 
20100126 

Bhavya pose la question : Dear Sir/Ma'am,
I read in the text book that the growth rates of these 3 functions are as below
n^{2/3} < n/lg n < n^{0.99}
I tried the substitution method to check the correctness of this. But it gets really tough as n increase.
Is there any simpler way to understand the correctness of these growth rates?
Thanks and Regards,
Bhavya Robert Dawson lui répond. 





541.39(1 + i)^15 = 784.09 
20091014 

Fitore pose la question : Hi, I noticed that this question was already posted up, however I was hoping I could solve it without having to use logs. Can you please help me? The equation is:
541.39(1 + i)^15 = 784.09 Penny Nom lui répond. 





Exponential form 
20090805 

motaz pose la question : Let x = log_2 1/8 Write the exponential form of the equation and solve the equation for x Stephen La Rocque lui répond. 





Log_7 (4X) = Log_14 X 
20090708 

Mukulu pose la question : Help me with this question because i tried my level best to get the right answer but i failed Log_7 (4X) = Log_14X Stephen La Rocque lui répond. 





Possible Values of a Base of a Logarithm 
20090605 

nazrul pose la question : If log base x of 25=2 then what is the value of x?
I am confused if the result be 5 or 5.
Please explain.
Thank you. Robert J. Dawson lui répond. 





(logx)squared + log (xcubed ) +2 =0 
20090519 

michael pose la question : Solve for x: (logx)squared + log (xcubed ) +2 =0 Penny Nom lui répond. 





The sides of a parallelogram 
20090317 

Sami pose la question : If ABCD is a parallelogram, prove that line AB is congruent to line CD. Clearly state your reasons and conjectures. Penny Nom lui répond. 





A property that decreases in value every year by 10 percent 
20090307 

PEter pose la question : there is a competition problem where a cottage is worth 25000 years, but it decreases in value every year by 10 percent. Without a calculator, is there a way to find after how many years, the cottage will be worth 2500? (besides multiplying it out and besides logs) Stephen La Rocque lui répond. 





An inequality with logs 
20090306 

Indrajit pose la question : (x/10)^(logx  2)<100..........how to solve this one?? Stephen La Rocque lui répond. 





If 5 to the power of y = 625, what is y? 
20090302 

Charlene pose la question : If 5 to the power of y = 625, what is y? Penny Nom lui répond. 





Frogs and kangaroos 
20090216 

Jenny pose la question : Albert, Bernard, Charles, Daniel and Ellie play a game in which each is a frog or kangaroo. Frogs' statements are always false while Kangaroos' statements are alwas true. 1. Albert says that bernard is a kangaroo. 2. Charles says that Daniel is a frog. 3. Ellie says that Alvert is not a frog. 4. Bernard says that Charles is not a kangaroo. 5. Daniel says that Elie and Albert are different kinds of animals. How many frogs are there? Penny Nom lui répond. 





6^x = y 
20090212 

Jamie pose la question : Find x:
6^x=y Harley Weston lui répond. 





The area of a triangle 
20090125 

black pose la question : Explain how the formula for the area of a triangle can be determined by using the formula for the area of a parallelogram. Penny Nom lui répond. 





650g+2kg+195g=how many kg 
20081211 

christian pose la question : 650g+2kg+195g=how many kg Penny lui répond. 





A quadrilateral with two pairs of congruent sides 
20081210 

nicole pose la question : what is the name of a figure that has 2 sides that measure 25 feet each and 2 sides that measure 10 feet each? Robert Dawson lui répond. 





A quadrilateral with exactly 1 pair of parallel sides and no congruent sides 
20081210 

alie pose la question : a quadrilateral with exactly 1 pair of parallel sides and no congruent sides is what? Robert Dawson lui répond. 





A log base 2 problem 
20081126 

dave pose la question : solve for x
(log base 2 of x)  (log base 2 of (x2)) = 3 Penny Nom lui répond. 





Symmetries of a parallelogram 
20081124 

anisha pose la question : how many lines of symmetry does a parallelogram have. A square and a rect are a
parallelogram too. so it is confusing?? pls help Walter Whiteley lui répond. 





How do you solve "logx^4=4? 
20081117 

Scott pose la question : How do you solve "logx^4=4"? Penny Nom lui répond. 





Scaling a logo 
20081020 

Carl pose la question : Hello!
I hope that you can help me out here. I've been trying to figure this out for awhile now and can't come up with the answer logically.
I am a graphic designer by trade and need to figure out how large my client's logo should be.
The logo will need to be sized proportionally with the surface area of the page.
The logo will always be sized at 1.2938(w) x .75(h) on a letter size page (8.5 x 11).
My question is...
When you increase the size of the page (not always proportionally sized  dimensionally) how do figure out the NEW size of the logo.
I could have a page 20" x 40" or 30' x 4'... or ANY size really.
I believe I have the new surface area of the logo but can't find the new dimensions. Harley Weston lui répond. 





Logs and exponentials 
20081006 

Charles pose la question : I seem to remember you could solve exponential problems using natural logs quite simply without calculators, such as the fifth root of 400 or 33 to the 4th power. All you did was convert the number to its natural log and then just divide by 5 or multiply by 4 and then convert it back. I just remember how to do this. Thanks. Harley Weston lui répond. 





4^x = 2^x + 12 solve for x 
20081002 

Dave pose la question : 4^x = 2^x + 12 solve for x. Harley Weston lui répond. 





An Euler diagram and a logic argument 
20080918 

Regina pose la question : Use a Euler diagram to determine whether the following argument is valid or invalid.
No wizard can yodel
All lizards can yodel
No wizard is a lizard Penny Nom lui répond. 





What is the derivative of (2^sinx)/(logbase4(2x+1))? 
20080916 

Jesse pose la question : What is the derivative of (2^sinx)/(logbase4(2x+1)) Harley Weston lui répond. 





Solving Exponential Equations Using Logarithms 
20080915 

Todd pose la question : 7(6^x)=6e^2x Janice Cotcher lui répond. 





2^x = 1,000,000 
20080906 

Peter pose la question : How do I solve for "x" in the following equation: "2 to the power of x = 1,000,000" ? Penny Nom lui répond. 





Solve e^x + e^(x+1) = 250 
20080825 

Laura pose la question : "solve this equation correct to three decimals"
e^x + e^x+1= 250 Penny Nom lui répond. 





Solving with the Natural Log 
20080728 

CB pose la question : I am trying to solve lnx +3ln2 = ln 2/x. Every way I've tried when I go to plug in the solution it doesn't come out right. Penny Nom lui répond. 





A hexagon has 3 parallelograms 
20080721 

Stephanie pose la question : A hexagon has 3 parallelograms but I am unsure of how to cut a hexagon into 3 parallelograms. Can you show me what this would look like? Harley Weston lui répond. 





Write log_2 (1/8) = 3 in exponential form 
20080627 

Jaime pose la question : how do you write log2 (1/8) = 3 in exponential form?
the 1/8 is a fraction and the 2 is a base of 2 Penny Nom lui répond. 





The angles of a parallelogram 
20080611 

light pose la question : ABCD is a parallelogram. If angle A. = (4x=17)degrees and angle B. = (3x5)degrees , what is angle c? Penny Nom lui répond. 





limit x>0 (logxlog(x1)) 
20080522 

kritica pose la question : lt x>0 (logxlog(x1)) Harley Weston lui répond. 





Which is larger, 727464^512693 or 624610^518548? 
20080518 

Yahweh pose la question : Lets say I have two very large numbers in the form of a^b:
727464^512693 and 624610^518548
I want to calculate which number is larger, but its unreasonable to type these numbers into a spreadsheet to get an answer right away. How could I determine the larger or the two numbers efficiently? Stephen La Rocque lui répond. 





The inverse of a function 
20080503 

keith pose la question : please help me find the inverse of this function:
h(t) = 2 + 4 ln(15t) Stephen La Rocque lui répond. 





Naming a figure 
20080424 

P. pose la question : What is the name of a figure that has 2 sides that measure
25 feet each and 2 sides that measure 10 feet each? Penny Nom lui répond. 





log2x+log(x+4)=1 
20080412 

ryan pose la question : solve the equation for x, log2x+log(x+4)=1 Penny Nom lui répond. 





1(1P)^75=0.05 
20080405 

Amy pose la question : 1(1P)^75=0.05 Stephen La Rocque and Penny Nom lui répond. 





The distance between the sides of a parallelogram 
20080330 

jhon pose la question : Calculate the perpendicular distance between AB and DC of a parallelogram. Note: AB and DC are the sides of the parallelogram. Penny Nom lui répond. 





A puzzle about hats 
20080303 

Sylvia pose la question : There were 4 people sitting in a row, truing to win $50.00 from a riddle.
The one in front was wearing a red hat.
The second from the front was wearing a blue hat.
The third from the front was wearing a red hat.
The last was wearing a blue hat and is blindfolded.
Each of them were informed that they are all wearing a hat,
the last person is blindfolded and that there are 2 red and 2 blue hats. If they can guess the
colour of their hat, then they win the prize.
There was a long silence, then one of them guessed the color of his hat correctly. Who was it?
and explain why.
(note that they can only see the person in front of them and are not allowed to turn around and
see behind them.) Penny Nom lui répond. 





Prove (p & ~q) v p = p 
20080212 

Tom pose la question : Prove (p & ~q) v p = p
Do I need to use the absorption law p v (p & q)=p? If yes,how do I cope with the NOT(~) in q?Thank you. Harley Weston lui répond. 





The interior angles of a parallelogram 
20080129 

amber pose la question : the measure of one interior angle of a parallelogram is 42 degrees more than twice the measure of another angle. Find the measure of each angle. Penny Nom lui répond. 





Volume of a log 
20080129 

Reji pose la question : i purchased a teak wood length 20feet and perimeter 60inch. How much cubic feet will be the wood. Stephen La Rocque lui répond. 





The interior angles of a parallelogram 
20080128 

steffie pose la question : How do you calculate the interior angle sof a parallelogram? Penny Nom lui répond. 





A parallelogram and a rhombus 
20080122 

miguel pose la question : i have a problem proving a parallelogram a rhombus.. if a diagonal of a parallelogram bisects an angle
of the parallelogram , then its a rhombus
prove Stephen La Rocque and Walter Whiteley lui répond. 





Two logic problems 
20071207 

Grace pose la question : 1. You are an archaeologist that has just unearthed a longsought triplet
of ancient treasure chests. One chest is plated with silver, one with gold,
and one with bronze. According to legend, one of the three chests is filled with
great treasure, whereas the other two chests house a maneating python that
can rip your head off. Faced with a dilemma, you then notice that
there are inscriptions on the chests:
Silver Chest  Treasure is in this Chest.
Gold Chest  Treasure is not in this Chest.
Bronze Chest  Treasure is not in the Gold Chest
.
You know that at least one of the inscriptions is true,
and at least one of the inscriptions is false. Which chest do you open?
(a) Silver (b) Gold (c) Bronze Penny Nom lui répond. 





ln (x)  x = ln (2) 
20071118 

James pose la question : How do you make x the subject of
ln (x)  x = ln (2) Stephen La Rocque lui répond. 





0 = (1/t)  [ln(1+r) ln(t)] 
20071018 

Brandi pose la question : Objective: solve for t, where r = 0.05
0 = (1/t)  [ln(1+r) ln(t)] Penny Nom lui répond. 





Irrational functions 
20071001 

alicia pose la question : i have a question about irrationals functions.
i have been using them quite some time now, but i wonder where they can be found in daily life?
i hope you can help me, Harley Weston lui répond. 





x= (y/z)ln((1+a^2)/(1a^2)) 
20070926 

John pose la question : If
x= (y/z)ln((1+a^2)/(1a^2))
Please solve for 'a'
Thanks in advance! Penny Nom lui répond. 





Finding a geometric mean and taking its antilog 
20070827 

Jack pose la question : Would like to know the basic geometric mean calculation. Also how would I take the antilog from this number? Stephen La Rocque lui répond. 





Logs and exponentials 
20070731 

Marsia pose la question : Explain how the functions of exponents and logarithms relate to each other. Penny Nom lui répond. 





The graph of a log function 
20070730 

Marsia pose la question : How would you describe to another student what the graph of a logarithmic function looks like? Penny Nom lui répond. 





Proving a quadrilateral is a rectangle 
20070714 

Sonja pose la question : I was having this discussion with another teacher and we need a third opinion. When you are trying to prove a quadrilateral is a rectangle which method should you use:
 Prove the shape is a parallelogram by doing slope 4 times by stating that parallel lines have equal slopes. Then proving a right angle by stating that perpendicular lines have negative reciprocal slopes.
 Doing the slope 4 times and stating that the shape is a rectangle because opposite sides are parallel because of equal slopes and it contains a right angle because of negative reciprocal slopes.
I guess the real question is do you have to first state that the shape is a parallelogram? Stephen La Rocque lui répond. 





log_{a} b + log_{b} a < 0 
20070708 

Claire pose la question : Suppose a, b are real numbers taking all positive values except 1, determine (without the use of calculators) whether there exists values of a and b such that log_{a} b + log_{b} a < 0 Penny Nom lui répond. 





log(0.81) 
20070628 

Ade pose la question : If log 3 = 0.477 . The answer of log 0.81 Harley Weston lui répond. 





Log base 2 of log base 2 of x 
20070627 

alex pose la question : y = log base 2 of lag base 2 of x
The slope of the tangent to the given curve at its xintercept is..? Harley Weston lui répond. 





Exponential form: x^y 
20070622 

Kishor pose la question : whats the easy way to calculate X raised to Y where y is much greater than x. Stephen La Rocque lui répond. 





The law of sines 
20070609 

Felicia pose la question : A parallelogram has one side that is 12.0 cm and one angle that is 65°. The shorter diagonal is 25.0 cm. To the nearest tenth of a centimetre, how long is the other side of the parallelogram? Use the sine law. Penny Nom lui répond. 





Converting mass and volume of water 
20070510 

Shian pose la question : Hello please help, I just can't seem to get the convertion thing and my mom tried to help but I still don't get it. How many grams does 1 milliliter of water weight? I was told 1g. How many grams does 0.1 liter of water weight? I was told 0.1g. Can you tell me if the answers given are correct with an explaination that I can understand? Thank you. Stephen La Rocque lui répond. 





Understanding log equations 
20070510 

Sean pose la question : The number, N, of people who have heard a rumor spread by mass media at time, t, in days is modelled by N (t) = a / 1+ be^ kt. If 50 people have heard the rumour initially and 300,000 people hear the rumour eventually, find a and b. If the rumour is initially spreading at the rate of 500 people per day, find k. Penny Nom lui répond. 





What is the limit of 3.x^(3/x) as x approaches +infinity? 
20070411 

Teodora pose la question : What is the limit of 3.x^3/x as x approaches +infinity ? Haley Ess lui répond. 





Logarithms 
20070409 

Emi pose la question : Given log10 2=0.30 and log10 3=0.47
How to i express 6 x 10power 14 in logarithm answer.
Please help me.
Thank you.
Emi Stephen La Rocque lui répond. 





A logarithm of a product and the product of logarithms 
20070227 

Sharon pose la question : Can you please explain Explain the difference between a logarithm of a product and the product of logarithms and give examples of each? Stephen La Rocque and Penny Nom lui répond. 





Centimeters to cubic meters and grams to kilograms 
20070214 

Colleen pose la question : A box of balls measures 120cm by 20cm by 20cm and weighs 48 g. One thousand boxes = x cubic meters and weighs x kilograms. Also, one million boxes = x cubic metes and weighs x kilograms. One billion boxes = x cubic meters and weighs x kilograms. Solve for x. Stephen La Rocque lui répond. 





The interior angles of a parallelogram 
20070207 

jenniffeir pose la question : Can a parallelogram have two 45 degree angles and two 75 degree angles? Haley Ess lui répond. 





The diagonals of a parallelogram are mutually bisecting 
20070121 

Greta pose la question : I am having trouble proving that the diagonals of a parallelogram are mutually bisecting. Penny Nom lui répond. 





Two consecutive angles of a parallelogram 
20070117 

Veronica pose la question : The measures of two consecutive angles of a parallelogram are in the ratio 9:11. Find the measure of each angle. Penny Nom lui répond. 





A problem involving logs 
20061126 

Beth pose la question : any help would be appreciated on how to solve without using the change of base formula for logarithms in the solution and check of the solution!!!
log256 (x) + log16 (x) + log4 (x) + log 2 (x) = 7/4 Stephen La Rocque and Penny Nom lui répond. 





An angle in a parallelogram 
20060813 

Sam pose la question : Parallelogram ABCD has diagonal AC equal in length to side AB. CD is produced to E so that D is between E and C. If angle BAC =30 degrees find the size of angle ADE. Stephen La Rocque lui répond. 





How many digits are in the number 2^64? 
20060614 

Trang pose la question : How many digits are in the number 2^{64}? Stephen La Rocque lui répond. 





The area of a parallelogram 
20060312 

Shayne pose la question : Is there a method of finding the area of a trapezium or/and parallelogram even if the height is not given? Could you also explain how to find the height? Penny Nom lui répond. 





What names are known for the quarter circle shape? 
20060306 

Christina pose la question : What names are known for the quarter circle shape? Stephen La Rocque and Penny Nom lui répond. 





An equation involving logarithms 
20060305 

Chris pose la question : Given that log_{e} y = 0.3log_{e}x+1.2 show that y=3.32 x^{0.3}
Penny Nom lui répond. 





6^(x+1) = 12^(x3) 
20060205 

BB pose la question : 6^{x+1} =12^{x3} Penny Nom lui répond. 





Who is lying? 
20060114 

Diane pose la question : A business man was working in his home office when he realized he had left a fivedollar bill in the book he had been reading. He called his butler to bring him the book from the library. When he got the book, the bill was no longer there. He then questioned the maid and the butler. The maid remembered seeing the bill between pages 99 and 100 in a book to the left of a business book. The butler did not recall seeing the bill, but was sure the book was to the right of the business book, because to the left of it there was a statistics book. Who is lying?
Penny Nom lui répond. 





Differentiation, powers and logs 
20060106 

Claudia pose la question :
Question: how do I find the derivative of
x* ln(x+(e^2))^2
x^lnx
x^(e^(x^2))
Penny Nom lui répond. 





A 24 sided polygon 
20051214 

Matt pose la question : I would like to know if there is a name for a 24 sided shape Penny Nom lui répond. 





Inclusive definitions 
20051214 

Layla pose la question :
recently the solvable quandary of 5+5+5=550 came up (the question says that you have to put 1 straight line somewhere in the equation to make it true with out turning the "=" into a "not=" sign).
So two answers were put forward:
545+5=550 (the use of a line converting a + into a 4)
AND
5+5+5(less than or equal to)550
There is currently an argument about the second solution. The disagreement is about whether this sign can be used. One person is arguing that the "less than or equal to" sign defines that the number on the left is in the range 550 and below. The other is saying that since the number (which is clearly defined with no variables) can never equal 550, then the "less than or equal to" sign cannot be used in this case.
Which one is the correct definition?
Walter Whiteley lui répond. 





Express t as a function of d 
20051130 

Matthew pose la question :
I have a problem on my homework I cant seem to figure out. Basically it gives me this Linear Regression Equation:
ln t=1.5 ln d0.8954
and it wants be to transform the equation expressing t as a function of d. For some reason I keep getting it wrong. Anyone got an idea of how to do this?
Penny Nom lui répond. 





Percent or percentage 
20051103 

Kenneth pose la question :
Which word should be used in the following?
Change a (percent or percentage) to a decimal.
Should the word percent be used only when a number precedes it as in 45 percent?
Harley Weston and Chris Fisher lui répond. 





cos x * cos 2x * cos 4x * cos 8x 
20050829 

Leandro pose la question :
A = cos x * cos 2x * cos 4x * cos 8x
What's the value of log A at base 2?
Chris Fisher and Penny Nom lui répond. 





y = log(x) + x. Solve for x. 
20050826 

Alain pose la question :
I have the following equation:
y = ln(x) + x
How do I solve for x?
Penny Nom lui répond. 





How many digits? 
20050607 

Floren pose la question : The numbers 2^{1989} and 5^{1989} are written one after another. How many digits in all are there? Claude Tardif lui répond. 





Logarithmic differentiation 
20050523 

Richard pose la question : I need to convince myself that I understand the process of
differentiating y=x^{x}.
The specific question is that if I have to take the logarithm of both sides
of the equation how can differentiate the following?
y= {(x+2)^{(x+2)}}/{(x+1)^{(x+1)}}  {(x+1)^{(x+1)}}/(x^{x}),
I have an idea that the differential of this fairly complex function
is itself ... am I right or wrong. Penny Nom lui répond. 





A torus and a sphere 
20050327 

Tony pose la question : Is it possible to shrink a torus into a sphere? Andrei Volodin and Penny Nom lui répond. 





Trading fish for bread 
20050225 

Mike pose la question : Byron lives where people trade goods they produce for other things they
need. He has some fish and wants to trade them for bananas. He finds
the following:
5 fish = 2 loaves of bread
6 oranges = 2 melons
1 loaf of bread = 1 banana and 3 oranges
4 loaves of bread = 14 oranges
How many bananas can Byron get with 5 fish? Penny Nom lui répond. 





arcsech x 
20050210 

Monica pose la question : Prove that arcsech x = ln[(1 + (1x^{2})^{(1/2)}) / x ] Penny Nom lui répond. 





Extraneous solutions 
20050204 

Heather pose la question : My teacher wants to know why there are extraneous solutions in logarithms? Penny Nom lui répond. 





Some logarithm problems 
20050127 

Jo pose la question : Given ln x=7.1; ln y=8.2, Find ln(x^3y^7) Penny Nom lui répond. 





ln(hx+n) 
20050107 

Anibal pose la question : if I have the eq.
y=hx+n
and I want to know ln(y), how do I process
ln(hx+n)? Penny Nom lui répond. 





A line from the center of the patch to the periphery 
20050101 

Sandrine pose la question : I am currently researching a patch disease of grasses. These patches are roughly circular. I need a term for a line from the center of the patch to the periphery. Since the patches are not perfectly circular, my supervisors tell me I cannot use the word 'radius'. What else could I use? Denis Hanson and Harley Weston lui répond. 





e = ln(b/a) solve for a 
20041201 

Daniel pose la question : I am trying to make "a" the subject of this equation "e = ln(b/a)" but am not sure if i'm doing it right. Any help would be appriciated, Claude Tardif lui répond. 





Crossing a river 
20040909 

Barb pose la question : Nine men and two boys, trekking through the jungle, need to cross a river. They have a small inflatable boat and it's easy enough to row it across the river. The boat, however, can hold no more than one man or the two boys. How can they all get across? (Hint. suppose there was only one man and two boys) Does it make math sense and what would the answer be Penny Nom and Claude Tardif lui répond. 





Two problems 
20040802 

JJ pose la question : A question on my homework assignment about logs says "suppose that x=logA and y=logB & write the expression in terms of x and y"
log(A  B)
Is this even possible? It seems like a typo.
Another is: "solve for t."
12(1.221)^t = t + 3
Is this one possible? If it is, I cant figure it out. Penny Nom lui répond. 





A parallelogram 
20040730 

Keith pose la question : I'm a high school student and have been having trouble with this problem , which is based on one pair of parallel sides of a parallelogram: If AD = 6x5 and BC = 3x+7 find x. Of course both sides have to be equal. Now I know the value of x is 4 So my question is how do you get 4 from the given information. Penny Nom lui répond. 





12(1.221)^t = t + 3 
20040714 

Jay pose la question : This problem has me stumped since i cannot separate the t and the 3. Here it is:
12(1.221)^{t} = t + 3
It's on a logarithm worksheet, but how do i figure it out?! Harley Weston lui répond. 





(ln(50/x)) / (ln(40/x)) = a 
20040621 

Un eleve pose la question : (ln(50/x)) / (ln(40/x)) = a = constante
comment extraire la variable x ??? Claude Tardif lui répond. 





Logs 
20040229 

Sandy pose la question : find X
3/2logb41/2logb8+logb2=logbx
my book uses prop 7 to rewrite as
logb4raised3/2logb8raised2/3+logb2=logbx; then writes
logb8logb4+logb2=logbx how did it get here? Claude Tardif lui répond. 





A problem with logs 
20040222 

Caitlyn pose la question : problem: ln x + ln (x2) = 1
I can solve this on the calculator, but the book wants 1+ [(sqroot)1+e]. How can I get the e? Penny Nom lui répond. 





Logarithms 
20040201 

A student pose la question : Where did the word logarithmic come from? Where/whom did it originate? Harley Weston lui répond. 





Making a windmill 
20040102 

Matthew pose la question : I am a farmer in Ontario. It has been almost 20 years since high school. I am toying with making a windmill. The output chart for the the old generator I have is shown below. Before I tear it appart I would like to develop a formula from the chart that can predict the output at various speeds. Penny Nom lui répond. 





Domain of a function 
20031014 

Karim pose la question : Find the Domain of the Function H(x) = Log3 (4x + 7)10 H(x) = log base 3 times 4X plus 7 minus 10 i am having problem solving these kinds of problems. Penny Nom lui répond. 





Applications of logarithms 
20030916 

A student pose la question : I have a project due in my algebra two class dealing with logs and where they are used in life, but I am having trouble finding websites that relate. So I would really appreciate it if you couldhelp me. Penny Nom lui répond. 





Terminology 
20030831 

Maria pose la question : My daughter Veronica is a rising 6th grader and has to complete some Summer Math assignments and would like to ask you three questions:  ___________ are number pairs that have a product of 1.
 You can name any point on a plane with two numbers. These two numbers are called _____________.
 A _______________ is the size of a cube that is exactly 1 inch on each edge.
Thanks, Penny Nom lui répond. 





Natural logarithms 
20030722 

Amanda pose la question : I'm going into my senior year of high school. I will be taking AP calculus, and my teacher gave us some homework over the summer. However, there are two things that I do not understand how to do. The first is, she wants us to be able to generate a unit circle by hand using 30, 60 and 90 degree triangles. I have used the unit circle in trigonometry, however I was never taught how to draw it. Secondly, I need to know how to do natural logarithms without a calculator. I was not taught how to do this, and the worksheet I was given only showed me how to complete them using a calculator. Claude Tardif lui répond. 





Solve x = y^z for z 
20030628 

Nathan pose la question : If x = y^z is there a way to solve for z, if x and y are given, without guessing or already knowing the answer?
ie: 64 = 2^z 6 is the obvious value for z. Is there a way I could solve for this variable using a formula, which would also apply when more complex values were substituted for x and y? Penny Nom lui répond. 





R= 5.3lnx + x. 
20030511 

A student pose la question : Reaction R to a dose x is given by: R= 5.3lnx + x. For a certain drug, R must not exceed 21. Show that a dose between 8 and 12 units satisfies this requirement & find, correct to 5 decimal places, the greates value of x which satisfies this condition? Harley Weston lui répond. 





Jo's books 
20030407 

Miguel pose la question : Jo announces, "I have more than 999 books." Jean says: "No Jo! You have fewer than 1,000 books." Mary says: "Jo has at least 1 book." Only one of these statements is true. How many books does Jo own? Penny Nom lui répond. 





The area of a parallelogram 
20030406 

A student pose la question : Find the area of the parallelogram with vertices (0,0),(7,2),(10,7),(3,5) Penny Nom lui répond. 





Division names 
20030310 

A parent pose la question : what is the answer to a division problem called Penny Nom lui répond. 





Can a square be a rhombus? 
20030304 

Beth pose la question : Can a square be a rhombus? Some sources say yes, some say no. Some sources define a rhombus as a quadrilateral and parallelogram with equal sides, but without right angles. Some sources say a square is a special case of a rhombus. Clarity, please! Walter Whiteley lui répond. 





Can a square be considered a rectangle? 
20030227 

Carla pose la question :
Can a square be considered a rectangle? (since opposite sides are same length and parallel) Would a regular hexagon or octagon be considered a parallelogram since its opposite sides are parallel? or does a parallelogram HAVE to have only 4 sides? Penny Nom lui répond. 





Radians 
20030116 

Erikson pose la question : I am a student in the 10th grade and attending advanced math at my high school. I was assign to do a report about the unit circle and the radian. But there seems to be no information available about the history of the radian; who first found out about them, which civilizations used it if any. Well, hopefully you'll assist me in this troubling question. Thank you for your kind consideration. Penny Nom lui répond. 





NO REDHATTED DWARVES ALLOWED 
20030114 

Dulce pose la question :
There are 1000 dwarves in Dwarfland. Now as you know, dwarves are born with either red or white hats on. The dwarves in Dwarfland love to party. Every night, they all flock to the same club to dance the night away. One day, a sign is posted at the club: "NO REDHATTED DWARVES ALLOWED". A certain number of days pass, after which all of the whitehatted dwarves are in attendance,and none of the reds. How did the red hats know not to come? Assumptions:  The number of red and whitehatted dwarves need not be equal. There are at least 1 of each color.
 There are no reflections or mirrors in Dwarfland (i.e. the dwarves can't see the color of their own hat), and no dwarf can reveal through direct or indirect means the color of another dwarf's hat.
 There is NO COMMUNICATION among dwarves
 No whitehatted dwarf ever misses a night of partying
Claude Tardif lui répond. 





A rope trick 
20021205 

Jerry pose la question : My name is Jerry and I am a math teacher at the secondary school level in the greater Toronto area. I posed the following problem to my enriched grade 10 math class that I found in the book called "Mathematics and the Imagination" by William Kastner. According to the author, it is posible for two people linked to each other with two ropes around their hands, to separate themselves without letting go of the rope. The students had lots of fun trying to accomplish this problem using skipping ropes from the Phys Ed department, but with no success. Penny Nom lui répond. 





Three bags of marbles 
20021108 

A student pose la question : I have 3 bags of marbles 1 bag is labeled blue; 2nd bag is labeled red; 3rd bag is labeled blue & red all the bags are mismarked your job is to take one marble from 1 bag look at it and correctly label all the bags Penny Nom lui répond. 





8 squares from 12 sticks 
20021008 

A student pose la question : If you have 12 sticks the same size, how do you make them into 8 squares? Claude Tardif lui répond. 





The community garden 
20020908 

Michele pose la question : Bryce, Duanne, Juliana and Sonya share a 40ft by 48 ft rectangular portion of the community garden in the neighborhood. With this space each has their own rectangular garden plot. Bryce is the only one with a square plot. its are is 1/2 the area of Duanne's The area of Bryce's plot is 2/3 the area of Julianna's plot. Their plots have one side in common. Sonya's garden has an area twice that of Julianna's garden. What are the dimensions of each person's garden plot? Leeanne Boehm lui répond. 





Parallelograms 
20020821 

Moorthy pose la question : 11 parallel lines are intersected by another 9 parallel lines.Then how many parallelograms are formed? Walter Whiteley lui répond. 





20 men dig 40 holes in 60 days 
20020724 

Lindsey pose la question : 20 men dig 40 holes in 60 days. So, 10 men can dig 10 holes in how many days? Penny Nom lui répond. 





Conversion of units 
20020429 

Matt pose la question : I am having trouble finding a workable equation for the following problem, particularly the conversion of two systems of measurement. The question states that there are 27 grams of salt in a kilogram of seawater. And it asks how many tonnes (1 tonne = 1000 kilograms) of salt are there in one cubic kilometer of ocean. It also says that the density of seawater is 1.1 g/cm3. What is the equation and how do I figure out how many kilograms there are in a cubic kilometre? Harley Weston lui répond. 





Logico mathematical knowledge 
20020123 

A teacher pose la question : How does young children's logico mathematical knowledge develop? Walter Whitely lui répond. 





The probability that the area of a triangle is smaller that 1/8 
20011221 

Hoda pose la question : Given unit square pick two points on adjacent sides of the square , what is the probability that the area of the resulting triangle is smaller that 1/8? I tried to tackle the problem by first sketching a square with the four vertices at (0,0), (1,1), (0,1) and (1,1). The answer seems to be the area under the curve y=0.25/x between 1 and 0, but how can you integrate such a function when ln0 is undefined? any help would be highly appreciated. Andrei Volodin lui répond. 





Normal lines 
20011211 

Kristie pose la question : Why are perpendicular lines called normal lines? Chris Fisher lui répond. 





Applied geometry 
20011102 

Jenny pose la question : Where can I find some handson activities for my Applied Geometry classes? I want to do more activities with them that allow us to get out of the classroom. However, I want to use activities that use only inexpensive equipment because I usually buy the equipment myself. Walter Whiteley lui répond. 





Who owns what pet? 
20011003 

A parent pose la question : Don, Frank, Jenny, and Ken each come from one state, either Alaska, Maine, Montana, or Oklahoma. They each speak one primary language, either English, french, Russian, or Spanish. And they each have one of four pets, a chinchilla, a dog, a hamster, or a turtle. Figure out which language and what pet each of the four people have, using the following clues. . . . Judi McDonald lui répond. 





300 pounds 
20010912 

Cassie pose la question : HOW MANY KILOS IS IN 300 POUNDS? Penny Nom lui répond. 





1996^1999 and 1999^1996 
20010729 

Rajesh pose la question : what is greater 1999^{1997} or 1997^{1999}? Chris Fisher lui répond. 





Two log problems 
20010616 

A student pose la question : Hi..this is one of 9th grade student in Fort Worth TX. well..I am doing EPGY stuffs in my school right now..and.. me and my teacher had problems to solve some advanced logarithmic thing. so I searched some sites to solve these two questions  (log base 7 * 10) * (log base 10 * X ) = 2
 log base 10 * (3x4) + log base 12 * X
 (log base 12 * 2) + (log base 12 * 5)
= log base 10 *4 Harley Weston lui répond. 





Taking matches 
20010505 

Mark pose la question : Two piles of matches are on a table. A player can remove a match from either pile or a match from both piles. The player who takes the last match loses. If there are two players, how should you play? Claude Tardif lui répond. 





Genealogy 
20010322 

Brian pose la question : In considering tracing genealogy the problem of a large and growing number of direct (grandparent) ancestors arose. Since the number of grandparents in any given generation doubles, for a person born in 2000 and assuming 25 year generations, in the year 1000 that person would have over one trillion direct ancestors in that year alone. Since estimates I have read place the total world population in 1000 at 250300 million, the one trillion figure cannot be correct. I must be missing something in my calculations. Can you help provide the answer? While I am unlikely to be able to trace back to 1000, there is reason to believe 1250 is possible. Even in that year there would exist over one billion direct ancestors. That is certainly rather daunting and unlikely to be achieved if correct. Penny Nom lui répond. 





How can you prove a quadrilateral to be a parallelogram? 
20010316 

Joy pose la question : How can you prove a quadrilateral to be a parallelogram? Walter Whiteley lui répond. 





P vs NP problem 
20010301 

Roy pose la question : What math journals would publish a proposed solution to the P vs NP problem when the work has been done by an amateur mathematician who has no degree in math? Claude Tardif lui répond. 





Faces 
20010221 

Sandy pose la question : How many faces are there on a sphere? What are the faces of a cone? What is the definition of a "face" of a 3D object? Walter Whiteley lui répond. 





Crossing the dessert 
20010129 

Zach pose la question : An Explorer needed to make a 5 day trip across a dessert. Each man with him could carry exactly 3 days food and water. For one man how many men will it take to cross the dessert? Claude Tardif lui répond. 





Derfs, Enajs and Sivads 
20010107 

John and Norman pose la question : All Derfs are Enajs. Onethird of all Enajs are Derfs. Half of all Sivads are Enajs. One Sivad is a Derf. Eight Sivads are Enajs. The number of Enajs is 90. How many Enajs are neither Derf nor Sivad? Penny Nom lui répond. 





An integration problem 
20001130 

A student pose la question : If a>0 and the integral from b to 0 of 1/(1+x) equals 1/2 the integral from a to 0 of 1/(1+x), express "b" in terms of "a" Claude tardif lui répond. 





Transporting bananas 
20001018 

Krystie pose la question : A farm has 45 bananas, a man has to take a truck and transport 15 bananas to a market that is 15 miles away. Every mile he travels, he must eat a banana. I have to get at least one banana to the market Penny Nom lui répond. 





Where will we use this in the real world? 
20001011 

Jane Ann Musgrove pose la question : As a teacher of mathematics, I am always asked "Where will we use this in the real world?". I am seeking ideas/sites via the internet where students can find answers to this type of question. Can you help me? To be more specific, right now I am interested in finding careers where the employees would use the concepts of "Radicals", "Matrices", and "Logarithms". This information will be used by students to make presentations to the class on their findings from internet searches. Harley Weston lui répond. 





Isolating an exponent 
20000924 

C. Scott pose la question : Suppose you invest $500.00 in an account that pays 10% interest compounded annually. How long will it take for this value to triple? A=p(1 + i)^{a} A=1500 i=0.1 1500=500(1.1)^{a} p=500 a=unknown How do you solve this problem algebraicly? How do you isolate the variable (a) when it is an exponent? Harley Weston lui répond. 





A proof that 1=2 
20000919 

sporky pose la question : Why does the proof for 1=2 not work? x = 1 x^{2} = 1 x = x^{2} 1 = 2x (derivitive) 1 = 2(1) 1 = 2 ??? please tell me where the false logic is. Walter Whiteley lui répond. 





Selling chickens 
20000912 

Rick pose la question : A man raised chickens. He sold all but 8 of them. The first buyer bought 1/3 of all the chickens + 2/3 of a single chicken. The second buyer bought 1/3 of the remaining chickens + 1/3 of a single chicken. The third buyer bought 1/3 of the remainder + 2/3 of a chicken. How many chickens did the seller own before selling any? All chickens were alive and whole when the buyers received them. Penny Nom lui répond. 





Logs and trig functions 
20000912 

Becky pose la question : How do they get these answers?  log 8 + log 2 = ?
Answer is: log 16
 For 0 degree < x < 90 degree, how many solutions are there for the equation 2sin x = cos x?
Answer: 1
Penny Nom lui répond. 





LOG(LN(x)) = 1 
20000728 

An algebra student pose la question : LET F(x)=LOG X AND G(x)= LN X. SOLVE (f *G)(x)= 1 SHOW COMPOSITION AND USE DEFINITION OF LOGS. Harley Weston lui répond. 





An equation involving x to the x 
20000722 

Joy Peter pose la question : I am joy, a teacher teaching Maths at the secondary level and while solving a sum came to this stage when i got x^{x} (1 + log x) = 0, by which we can conclude that x^{x} = 0 or 1 + log x = 0. If x^{x} = 0, than what should be the value of x? I feel that the value of x should then be 0 (zero) but then how do I explain this to the students as we also know that anything to the power of 0 is 1 but here 0 raised to 0 is 1. If this is not defined then how do I explain this? Penny Nom lui répond. 





Radioactive decay 
20000518 

Catherine Sullivan pose la question : Please help me with the following: The radioactive isotope carbon14 is present in small quantities in all life forms, and it is constantly replenished until the organism dies, after which it decays to carbon12 at a rate proportional to the amount of C14 present, with a half life of 5730 years. Suppose C(t) is the amount of C14 at time t.  Find the value of the constant k in the differential equation: C'=kC
 In 1988 3 teams of scientists found that the Shroud of Turin, which was reputed to be the burial cloth of Jesus, contained 91% of the amount of C14 contained in freshly made cloth of the same material. How old is the Shroud according to the data?
Harley Weston lui répond. 





The Village of Truth 
20000510 

Sean Pearson pose la question : Our teacher gave us a logic problem involving two villages: the village of truth, and the village of lies. The problem is in asking two guards the right question to gain entrance to the fenced compound the villages are in without being shot. Have you heard of this problem ? Harley Weston lui répond. 





Two calculus problems 
20000501 

Kaushal Shah pose la question : How Do WE Integrate the following Functions,  Integral xtanx dx
 How was natural base "e" discovered and why e=2.7.......
Claude Tardif lui répond. 





Logs 
20000412 

Jessica pose la question : Write as a single log 3ln x  2ln(y+e) + 5ln(x12)  4ln y Harley Weston lui répond. 





Compounding continuously 
20000321 

Gina pose la question : You deposit $1500 in an account that pays 6.5% annual interest, compounded continuously. Find the balance after 10 years. I'm not sure what to do with the "compounded continuously" part. Penny Nom lui répond. 





Characteristic of a logarithm 
20000314 

Andrew Strauss pose la question : What is the characteristic of log base 18 of 1980 ? Harley Weston lui répond. 





Congruent parts of congruent figures 
20000310 

Erica pose la question : Yesterday, I recieved a test problem asking to prove two line segments equal. Here is the problem as I was given it: Given: paralleogram ABCD AE is perpendicular to DB CF is perpendicular to DB Prove: AE is equal to CF I answered the problem as follows: . . . Walter Whiteley lui répond. 





Tennis doubles 
20000204 

Brittany Allinson pose la question : Cheri, Beth and Jacinta are daughters of Mr. Sullivan, Mr. Marchand, and Mr. Benoit. Four of these people are playing tennis doubles. Mr. Benoit's daughter and Mr. Sullivan are partners. Cheri's father and Mr. Marchand's daughter are also partners. There aren't any father/daughter combinations. Who is Cheri's father? Penny Nom lui répond. 





Logarithms 
20000118 

Jennifer pose la question :
Hi I have a test tomorrow and I was wondering if you could help me with these two problems. Explain how to express y in terms of x if log3y=4log3(2X) The LN key on your scientific calculator is not working, but the ex and LOG keys are. Write directions for calculating a natural logarithm using the ex and LOG keys. Explain why these directions will get you the right answer. Harley Weston lui répond. 





Capacitor discharge rate 
20000109 

Bill Phillips pose la question : I need to be solve for t in the following rate problem for an electrical capacitor. Vr = E(e^t/RC), e=nat. log 2.718 raised to the t/RC power. Harley Weston lui répond. 





Three algebra problems 
19991228 

Stephanie Branton pose la question :
 If P represents the product of all prime numbers less than 1000, what is the value of the unit's digit of P?
 Do any real numbers a and b exist such that: ln(a+b)=ln a + ln b? if so, what are they?
 Define a function by: f(x)=1/1x where x is not equal to 0,1. what is f(f(f(a)))?
Harley Weston lui répond. 





Logarithms 
19991216 

Pierre pose la question : Can you please answer those three question  inverse or the exponential function.
logx 81 = 4, x expo4 = 81, x = +or 4square root 81, x = +or 3 s.s = {3} Why is 3 not acceptable.  .
. . Harley Weston lui répond. 





Log Cancel 
19991203 

Justin Murray pose la question : Ok I feel like a goof because I know this and I cant think of an answer But I want to isolate the x in the function y=2^x how do I do this? Harley Weston lui répond. 





Two derivatives 
19991116 

Gina Renicker pose la question : The derivative of: y=e^{(xlnx)} and y=x^{2arctan(x1/2)} Harley Weston lui répond. 





Area of a circle and an inequality 
19991030 

Adam Anderson pose la question : I have two problems. The first: prove that the area of a cirlce is pi times radius squared without using calculus. The second: show that ln(x) < x  1 for all x > 0. Harley Weston lui répond.






Derivatives with logs 
19991026 

Kate pose la question : What is the derivative of 5 to the 5x2 at x equals 0.8? Harley Weston lui répond. 





log(a) 
19991022 

Brenda Miskimmin pose la question : I need to know the mercury concentration in mg/L or ng/L for the following: log M (Hg) = 8.5 where mw of Hg=200.59 (it's the negative sign in front of log that confuses me). Harley Weston lui répond. 





Solving using logs 
19991011 

Rich Bolton pose la question : Here's my question: $541.39(1+i)^{15}=784.09 Can you please show me how to do this? Penny Nom lui répond. 





Logic and mathematical logic 
19991006 

Polly Mackenzie pose la question : What is the difference between logic and math logic? Walter Whiteley lui répond. 





Jose and Arthur 
19990926 

Joel Hammer pose la question : Jose can run around the track in 40 seconds. Arthur runs with Jose but in the opposite direction. They meet every 15 second. How long will it take Arthur to make one trip around the track? Denis Hanson lui répond. 





Bales of hay 
19990913 

Ivy pose la question : You are given 5 bales of hay. Two bales are weighed at a time, which equal the following weights: 110, 112, 113,114,115,116,117,118,120,121. What does each individual bale weigh? Harley Weston lui répond. 





The three jugs problem 
19990902 

Kent Lane pose la question : I wonder if you could help me figure out this secondary Discrete Math Problem. I cannot figure out where this comes from. Here's the question: You have three containers. Container 1 is a three (3) liter container. Container 2 is a five (5) liter container. Container 3 is an eight (8) liter container that is full of liquid. The goal is to get 4 liters in one of the containers. Stipulations: There are no marks on the containers to measure out the liquid. All you know is that 1 is 3 l., 2 is 5 l., and 3 is 8 l. full of liquid. Chris Fisher lui répond. 





The Bellhop Problem 
19990829 

Gerard O'Neill pose la question : Three fellows going to a Math Conference book into a motel. "That will be $30.00" says the bellhop. Each fellow gives $10.00 and they go off to their room. The manager enters and says "That was a $25.00 room. Go and give them $5.00 back." The bellhop heads off but thinks....."how am I going to split $5.00 between 3 fellows? Hey I will keep two dollars and give each guy a dollar." He does just that.......each fellow now paid $9.00 and the bellhop kept two. 3 X 9= 27 plus the bellhops two = $29.00 Where is the missing dollar? Harley Weston lui répond. 





Crossing the Bridge 
19990827 

Debbie Walter pose la question : If you have four people who need to cross a bridge in the dark with only one flashlight and only two of them can cross at a time and their speeds of crossing are as follows:  one person can cross it in one minute
 one person can cross it in two minutes
 one person can cross it in five minutes
 and the slowest person can cross it in ten minutes
what is the shortest amount of time it would take to get all four across the bridge? Penny Nom lui répond. 





A log problem 
19990508 

N. Lam pose la question : I don't understand how to do this type of question: log(base absolute value x)y = log(base abs.val.x)2 + log(base abs.val.x)(Cos x) How do you graph the equation also, if 2(3.14)<=x<=2(3.14) Harley Weston lui répond. 





A 
19990502 

Leah pose la question : a=b a^2=ab a^2+b^2=abb^2 (ab)(a+b)=b(ab) a+b=b b 2=1 why is this proof wrong? Penny Nom lui répond. 





A Series 
19990420 

Deepak Shrestha pose la question : Given the sequence an=e^(n*Ln(n)), does the series converge and why? Harley Weston lui répond. 





Converting Metric Measurements 
19990408 

Rick pose la question : Do you have any simple explanations for converting Metric measurements to other Metric measurements?? What helpful hints do you also have for a 5th Grader... Penny Nom lui répond. 





Universal Area 
19990408 

Karen Richardson pose la question : I need a formula for area that works for a square, a rectangle, a parallelogram, a trapezoid, and a triangle. Jack LeSage, Chris Fisher and Harley Weston lui répond. 





Circumference and Area 
19990216 

Natalie pose la question : finding the circumference of a circle? formula finding the area of a parallelogram? formula
Penny Nom lui répond. 





John Napier and e 
19990206 

Shimin pose la question : I would like to ask about the exact definition of e, its history (like how John Napier came about discovering it) and its applications in problems and real life situations. Thank you! Chris Fisher lui répond. 





Logs 
19981021 

Benny pose la question : What does log means? How come we have to use log Chris Fisher lui répond. 





An Implication 
19980927 

Danielle Evans pose la question : i am in my second year of math for the liberal arts and a problem has be terribly confused.. can you answer this [(p > q) ^ (q > p)] > (p <> q) is this an implication?? i would love to hear your answer thank you... danielle evans Chris Fisher lui répond. 





Two Problems 
19980728 

James Pulver pose la question : How do you solve these problem? If log abc=16 and log ac=12 , find b. (The logs are log base 10.) and If a and b are real numbers, i^2 = 1 and (a+b)+5i=9+ai what is the value of b? Jack LeSage lui répond. 





A Logic Problem 
19980607 

Anthony Bacigalupo pose la question : My name is Anthony Bacigalupo and I take Sequential ][ Math and am taking a practice regents. When doing a logic problem, I encountered the following statements, where I am trying to prove P ( I left out steps unrelated to the question).... Chris Fisher lui répond. 





Isosceles trapezoid formula 
19980512 

Donna McMullin pose la question : The teacher of Gifted and Talented Math has been trying to locate the formula for anisosceles trapezoid and we can't find it anywhere. Could it be the same formula for that of a parallelogram ? Please advise. Walter Whiteley lui répond. 





Logic and Matrix Instruction 
19980424 

Robin Booker pose la question : I need assistance with instruction strategies to teach the construction of a matrix, solving a logic problem. Providing instruction in the construction of a simple matrix , no problem. However, I stumpted on this one. Five players were chosen as All Stars at the basketball banquet. Based on the following clues, find the player's name, team, uniform color and number of points scored.... Harley Weston lui répond. 





A Problem with Logs. 
19971126 

Herman pose la question : Given log 24=a, log 25=b and log 26=c, express log 39 in terms of a, b and c. Penny Nom lui répond. 





Natural Logarithm Functions 
19970423 

Rickson pose la question : The following two questions are some of my son's homework that he is having trouble with......any advice or assistance would be appreciated. (eX)5=1000.............the X and 5 are exponents lnx + ln(x+3) = ln10 In each question the problem is to find x. Harley Weston lui répond. 





The Division Bracket. 
19970409 

Judy Riley pose la question : A fellow teacher recently asked if I remembered the exact word for a division bracket (not the symbol with dots, the horizontal line in a fraction, or a solidus). I couldn't. Can you help? Walter Whiteley and Harley Weston lui répond. 





Smith, Rodriguez and Jones 
19961107 

Rafayel Ambartsumyan pose la question : On a train, Smith, Rodriguez, Jones are the fireman, brakeman, and engineer, but not in that order. Also aboard the train are three businessman who have the same names, a Mr. Smith, a Mr. Rodriguez, and a Mr. Jones. ..... Who is the engineer? Penny Nom lui répond. 





Pronunciation 
19960305 

Todd Stienhauser pose la question : Is 123.4 pronounced "one hundred and twenty three and four tenths"or "one hundred twenty three and four tenths"? Penny Nom lui répond. 

