93 articles trouvés pour ce sujet.
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A problem with logarithms |
2019-08-23 |
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Iriogbe pose la question : Find the value : if log3 (a-6) =2b and log2 (a-7) =3b Penny Nom lui répond. |
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4^x=2^x+6 |
2019-04-05 |
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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. |
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Double the number of pennies each week |
2019-02-28 |
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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. |
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y=lnx+(1+ln2)/2 and y=x^2 |
2019-01-28 |
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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. |
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4444^4444 |
2017-12-10 |
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Sashi pose la question : 4444 to power of 4444=?
Please share the result with simplification. Penny Nom lui répond. |
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The derivative of f(x)=2^x/x |
2017-11-28 |
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Chhavi pose la question : f(x)=2^x/x.
Find f'(x). Penny Nom lui répond. |
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3^2x-5=27 |
2016-12-14 |
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danaja pose la question : solve for the following 3^2x-5=27 Penny Nom lui répond. |
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Find two values of x satisfying f(x)=1 where f(x)=sin(ln(x)) |
2016-01-21 |
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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. |
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Manipulating an expression using logarithms |
2015-05-18 |
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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. |
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logbase4 (sin x) = -0.5 |
2014-10-26 |
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Susan pose la question : Solve for x: logbase4 (sin x) = -0.5 Penny Nom lui répond. |
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Logarithms |
2014-08-28 |
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effaryna pose la question : how logarithms is applied in everyday life? Penny Nom lui répond. |
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Differentiate ln[x(2x-4)^1/2] |
2014-06-28 |
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Igwe pose la question : If y=In[x(2x-4)^1/2],find dy/dx at x=3 Penny Nom lui répond. |
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How do we use logarithms in our daily life |
2014-06-01 |
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ss pose la question : how do we use logarithms in our dailylife Penny Nom lui répond. |
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Evaluate log3 14 |
2013-11-17 |
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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. |
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4=(1+.08)^x |
2013-06-15 |
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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. |
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How do i write log_8(P) =7 in exponential form? |
2013-04-14 |
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nancy pose la question : How do i write this in exponential form log8P =7 Penny Nom lui répond. |
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Solve 8 logx > x |
2013-02-19 |
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Fulvio pose la question : Hi, could you solve this equation in algebraic form:
8logx>x Harley Weston lui répond. |
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What is the domain of f(x)=sin(ln(x))/ln(x)? |
2013-02-06 |
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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. |
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The exponential form of log8=P |
2012-04-25 |
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Kristina pose la question : what is the exponential form of log8=P Penny Nom lui répond. |
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A log equation in exponential form |
2011-11-11 |
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Sarah pose la question : Express the equation in Exponential form
log2 to the 16th power=4 Penny Nom lui répond. |
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Uses of logarithms |
2011-11-09 |
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BEA pose la question : what is the use of logarithmic functions in real life or daily life? Penny Nom lui répond. |
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Exponential form |
2011-05-18 |
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Kara pose la question : How do I write this in exponential form?
log 1/8 = -3 Penny Nom lui répond. |
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ln(12 x) = 6 |
2011-03-03 |
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Carolyn pose la question : solve the equation
ln12x = 6
Thank you
Carolyn Penny Nom lui répond. |
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Daily life example of logarithms |
2011-02-04 |
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owais pose la question : what are the application or daily life example of logarithms? Harley Weston lui répond. |
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Simplify the logarithmic expression |
2010-12-02 |
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Adori pose la question : Use the properties of logarithms to simplify the logarithmic expression. Log(1/250) base 5 Penny Nom lui répond. |
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An equation involving logarithms |
2010-09-27 |
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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. |
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y = - log(x) |
2010-04-28 |
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Alex pose la question : y= - log(x), where y = 4.3
solve for x. Harley Weston lui répond. |
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Log[f(x)] |
2010-03-08 |
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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. |
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Exponential form |
2009-08-05 |
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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. |
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Log_7 (4X) = Log_14 X |
2009-07-08 |
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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. |
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(logx)squared + log (xcubed ) +2 =0 |
2009-05-19 |
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michael pose la question : Solve for x: (logx)squared + log (xcubed ) +2 =0 Penny Nom lui répond. |
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A property that decreases in value every year by 10 percent |
2009-03-07 |
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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. |
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An inequality with logs |
2009-03-06 |
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Indrajit pose la question : (x/10)^(logx - 2)<100..........how to solve this one?? Stephen La Rocque lui répond. |
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If 5 to the power of y = 625, what is y? |
2009-03-02 |
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Charlene pose la question : If 5 to the power of y = 625, what is y? Penny Nom lui répond. |
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A log base 2 problem |
2008-11-26 |
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dave pose la question : solve for x
(log base 2 of x) - (log base 2 of (x-2)) = 3 Penny Nom lui répond. |
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How do you solve "logx^4=4? |
2008-11-17 |
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Scott pose la question : How do you solve "logx^4=4"? Penny Nom lui répond. |
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2^x = 1,000,000 |
2008-09-06 |
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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. |
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Solve e^x + e^(x+1) = 250 |
2008-08-25 |
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Laura pose la question : "solve this equation correct to three decimals"
e^x + e^x+1= 250 Penny Nom lui répond. |
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Write log_2 (1/8) = -3 in exponential form |
2008-06-27 |
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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. |
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limit x->0 (logx-log(x-1)) |
2008-05-22 |
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kritica pose la question : lt x->0 (logx-log(x-1)) Harley Weston lui répond. |
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Which is larger, 727464^512693 or 624610^518548? |
2008-05-18 |
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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. |
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The inverse of a function |
2008-05-03 |
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keith pose la question : please help me find the inverse of this function:
h(t) = 2 + 4 ln(1-5t) Stephen La Rocque lui répond. |
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log2x+log(x+4)=1 |
2008-04-12 |
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ryan pose la question : solve the equation for x, log2x+log(x+4)=1 Penny Nom lui répond. |
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1-(1-P)^75=0.05 |
2008-04-05 |
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Amy pose la question : 1-(1-P)^75=0.05 Stephen La Rocque and Penny Nom lui répond. |
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ln (x) - x = ln (2) |
2007-11-18 |
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James pose la question : How do you make x the subject of
ln (x) - x = ln (2) Stephen La Rocque lui répond. |
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Logs and exponentials |
2007-07-31 |
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Marsia pose la question : Explain how the functions of exponents and logarithms relate to each other. Penny Nom lui répond. |
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loga b + logb a < 0 |
2007-07-08 |
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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 loga b + logb a < 0 Penny Nom lui répond. |
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log(0.81) |
2007-06-28 |
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Ade pose la question : If log 3 = 0.477 . The answer of log 0.81 Harley Weston lui répond. |
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Log base 2 of log base 2 of x |
2007-06-27 |
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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 x-intercept is..? Harley Weston lui répond. |
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Understanding log equations |
2007-05-10 |
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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. |
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What is the limit of 3.x^(3/x) as x approaches +infinity? |
2007-04-11 |
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Teodora pose la question : What is the limit of 3.x^3/x as x approaches +infinity ? Haley Ess lui répond. |
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A logarithm of a product and the product of logarithms |
2007-02-27 |
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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. |
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A problem involving logs |
2006-11-26 |
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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. |
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How many digits are in the number 2^64? |
2006-06-14 |
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Trang pose la question : How many digits are in the number 264? Stephen La Rocque lui répond. |
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An equation involving logarithms |
2006-03-05 |
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Chris pose la question : Given that loge y = 0.3logex+1.2 show that y=3.32 x0.3
Penny Nom lui répond. |
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6^(x+1) = 12^(x-3) |
2006-02-05 |
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BB pose la question : 6x+1 =12x-3 Penny Nom lui répond. |
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Differentiation, powers and logs |
2006-01-06 |
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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. |
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cos x * cos 2x * cos 4x * cos 8x |
2005-08-29 |
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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. |
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y = log(x) + x. Solve for x. |
2005-08-26 |
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Alain pose la question :
I have the following equation:
y = ln(x) + x
How do I solve for x?
Penny Nom lui répond. |
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Extraneous solutions |
2005-02-04 |
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Heather pose la question : My teacher wants to know why there are extraneous solutions in logarithms? Penny Nom lui répond. |
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Some logarithm problems |
2005-01-27 |
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Jo pose la question : Given ln x=7.1; ln y=8.2, Find ln(x^3y^7) Penny Nom lui répond. |
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ln(hx+n) |
2005-01-07 |
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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. |
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Two problems |
2004-08-02 |
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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. |
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12(1.221)^t = t + 3 |
2004-07-14 |
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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. |
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(ln(50/x)) / (ln(40/x)) = a |
2004-06-21 |
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Un eleve pose la question : (ln(50/x)) / (ln(40/x)) = a = constante
comment extraire la variable x ??? Claude Tardif lui répond. |
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Logs |
2004-02-29 |
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Sandy pose la question : find X
3/2logb4-1/2logb8+logb2=logbx
my book uses prop 7 to rewrite as
logb4raised3/2-logb8raised2/3+logb2=logbx; then writes
logb8-logb4+logb2=logbx how did it get here? Claude Tardif lui répond. |
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A problem with logs |
2004-02-22 |
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Caitlyn pose la question : problem: ln x + ln (x-2) = 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. |
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Logarithms |
2004-02-01 |
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A student pose la question : Where did the word logarithmic come from? Where/whom did it originate? Harley Weston lui répond. |
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Domain of a function |
2003-10-14 |
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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. |
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Applications of logarithms |
2003-09-16 |
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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. |
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Natural logarithms |
2003-07-22 |
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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. |
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1996^1999 and 1999^1996 |
2001-07-29 |
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Rajesh pose la question : what is greater 19991997 or 19971999? Chris Fisher lui répond. |
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Two log problems |
2001-06-16 |
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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 * (3x-4) + log base 12 * X
--------------------------------------------------- (log base 12 * 2) + (log base 12 * 5)
= log base 10 *4 Harley Weston lui répond. |
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An integration problem |
2000-11-30 |
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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. |
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Where will we use this in the real world? |
2000-10-11 |
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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. |
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Logs and trig functions |
2000-09-12 |
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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. |
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Radioactive decay |
2000-05-18 |
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Catherine Sullivan pose la question : Please help me with the following: The radioactive isotope carbon-14 is present in small quantities in all life forms, and it is constantly replenished until the organism dies, after which it decays to carbon-12 at a rate proportional to the amount of C-14 present, with a half life of 5730 years. Suppose C(t) is the amount of C-14 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 C-14 contained in freshly made cloth of the same material. How old is the Shroud according to the data?
Harley Weston lui répond. |
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Two calculus problems |
2000-05-01 |
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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. |
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Logs |
2000-04-12 |
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Jessica pose la question : Write as a single log 3ln x - 2ln(y+e) + 5ln(x-12) - 4ln y Harley Weston lui répond. |
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Characteristic of a logarithm |
2000-03-14 |
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Andrew Strauss pose la question : What is the characteristic of log base 18 of 1980 ? Harley Weston lui répond. |
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Logarithms |
2000-01-18 |
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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. |
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Logarithms |
1999-12-16 |
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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. |
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Log Cancel |
1999-12-03 |
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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. |
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Two derivatives |
1999-11-16 |
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Gina Renicker pose la question : The derivative of: y=e(xlnx) and y=x2arctan(x1/2) Harley Weston lui répond. |
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Derivatives with logs |
1999-10-26 |
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Kate pose la question : What is the derivative of 5 to the 5x-2 at x equals 0.8? Harley Weston lui répond. |
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-log(a) |
1999-10-22 |
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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. |
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Solving using logs |
1999-10-11 |
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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. |
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A log problem |
1999-05-08 |
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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. |
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John Napier and e |
1999-02-06 |
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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. |
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Logs |
1998-10-21 |
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Benny pose la question : What does log means? How come we have to use log Chris Fisher lui répond. |
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Two Problems |
1998-07-28 |
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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. |
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A Problem with Logs. |
1997-11-26 |
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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. |
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Natural Logarithm Functions |
1997-04-23 |
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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. |
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