116 articles trouvés pour ce sujet.
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Input and output of a function |
2019-12-16 |
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Destanie pose la question : What is the output if the input is -1??? Penny Nom lui répond. |
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f(x + 2) |
2019-02-26 |
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a student pose la question : How do you use f(x) = 3x+1 to determine the transformed function of f(x + 2)? Penny Nom lui répond. |
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Composition of functions |
2019-02-24 |
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Joshua pose la question : Let g(x)=(x)^(2)+x-1
Find such a function f such that
(fog)(x)=(x)^(4)+2(x)^(3)-3(x)^(2)-4x+6 p lui répond. |
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Function notation |
2019-02-10 |
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Paige pose la question : What is the difference between f(x+2) and f(x)+2? 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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y = f(x) |
2018-12-30 |
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yogita pose la question : What is the actual meaning of "f(x)" ? Please give me full explanation Penny Nom lui répond. |
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y = |x| - 1 |
2018-11-30 |
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alexis pose la question : what does this mean y=|x|-1 Penny Nom lui répond. |
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f(x) and f(-x) |
2018-10-19 |
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Simran pose la question : what is difference between f(x) compared to f(-x) on graph Penny Nom lui répond. |
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The domain of f(g(x)) |
2018-06-18 |
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Joshua pose la question : What are the restrictions of the domain of f(g(x))? Penny Nom lui répond. |
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f(x)=-x^2-6x find f(x-2) |
2017-10-27 |
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Kenneth pose la question : f(x)=-x^2-6x find f(x-2) Penny Nom lui répond. |
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y = g(x + 1) |
2017-06-27 |
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Shamsudiin pose la question : HI there i am currently doing a level maths AS
I don't understand how to graph this Question y=g(x+1) i really need help please
please respond to this problem Penny Nom lui répond. |
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A linear relationship |
2016-10-16 |
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Bianca pose la question : x represents the number of hours since 8am. y represents the number of children the school nurse has seen during the school day. The nurse has seen 3 children by 8am and 27 children by noon.
How many children has the nurse seen at 2pm?
If the nurse has seen 18 children, what time is it? Penny Nom lui répond. |
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The temperature inside and outside a greenhouse |
2016-07-22 |
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Mehzad pose la question : Every day, the temperature in a greenhouse is at its low temperature, 70 degrees Fahrenheit, at 2 a.m. and at its high temperature, 84 degrees Fahrenheit, at 2pm. Its temperature increases linearly between 2 am and 2pm , and decreases linearly from 2 pm and to 2am. The outside temperature follows the same linear patterns, but has a low temperature of 60 degrees Fahrenheit at 2 am and a high temperature of 78 degrees Fahrenheit at 2 pm. At which of the following times will the temperature inside and outside the greenhouse be the same?
a) 8:00 am
b) 12:00 noon
c) 4:00 pm
d) The two temperatures will never be the same Penny Nom lui répond. |
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The composition of a function with itself |
2016-07-17 |
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Mel pose la question : If f(1 + 3x) = 1 * x, solve f(f(x)) Penny Nom lui répond. |
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find f+g |
2016-06-26 |
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yzabelle pose la question : find f+g
f(x)=x^2-1
g(x)=square root of x+2 Penny Nom lui répond. |
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sin 2x - sin x = 0 |
2016-04-24 |
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lilly pose la question : sin 2x - sin x = 0 0 Penny Nom lui répond. |
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The inverse of a function |
2016-03-20 |
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Billy pose la question : f(x) = Square root(x^2 + 2x)
What is the inverse? Penny Nom lui répond. |
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Fencing around a rectangular field |
2015-11-11 |
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Darlene pose la question : Question from Darlene, a parent:
A farmer has 10,000 meters of fencing to use to create a rectangular field. He
plans on using some of the fencing to divide the rectangular field into two
plots of land by constructing a fence inside the rectangle that is parallel to one
of the sides. Let X be the width of the rectangular field. Write an equation
to express the area of the field as a function of X. Find the value of X that
maximizes the area of the field. Penny Nom lui répond. |
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y=f(x) and y=-3/2f(x) |
2015-05-27 |
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Kevin pose la question : Could you please show me what change y=f(x) to y=-3/2f(x) has gone through and please graph.
y=f(x) points: (-3,0) ,(0,-2), (2,-2), (3,4)
how does (0,-2) change? Penny Nom lui répond. |
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A stone is dropped in a lake |
2015-02-14 |
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Wendy pose la question :
Hi, I have problems solving this problem. We didn't exactly go over these kind of problems and the book doesn't have an example either. Thank you for your help!
A stone is dropped in a lake, creating a circular ripple that travels outward at a speed of 80 cm/s.
(a) Find a function g that models the radius as a function of time t.
g(t) =
(b) Find a function f that models the area of the circle as a function of the radius r.
f(r) =
(c) Find f compose g.
f compose g = Penny Nom lui répond. |
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Graphing piecewise functions |
2014-03-29 |
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Rayven pose la question : Hi! I'm in eighth grade, taking ninth grade algebra 1. I'm confused as to how to
graph piecewise functions. I know that you have already answered a question similar to this
(I did my research first) but it didn't completely help me on my homework. I have to graph
piecewise functions for the specified domains, and create a table for the absolute values.
I know that two bars around a number means absolute value (two bars around -2 makes it +2)
, but how do I graph and chart the absolute value for the following:
f(x)= |x+3 | for -5≤x≤3
And then graph and chart: (on a separate graph):
f(x)= {x if x≤0
{x+1 if x <0
thank you!
~Rayven Penny Nom lui répond. |
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A limit with trig functions |
2014-02-22 |
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pearl pose la question : (what is the value of limit of x as it approaches 0 of sin8x divided by cos6x) Penny Nom lui répond. |
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What does y= f(x) actually mean? |
2013-12-31 |
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John pose la question :
I don't understand how to pick coordinates for y=f(x).
I took a look at your answer to a previous question here:
http://mathcentral.uregina.ca/QQ/database/QQ.09.00/monica2.html
What does y= f(x) actually mean? Penny Nom lui répond. |
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Inverse trig functions |
2013-05-19 |
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ky pose la question : hello, so iv'e been asked to draw a triangle with sides of 3, 4, and 5.
And find the measure of all three angle using sin-1, cos-1, tan-1.
I got really confuse, I'm taking the SAT pretty soon and it would be great
to get this... THANX 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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The continuity of f(x,y)=ln(x^2+y^2) |
2013-02-17 |
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anu pose la question : the question says we have to find the points in the plane where the function is continuous:
f(x,y)=ln(x^2+y^2) . here we aren't given a particular point (x,y) where we have to check a function's
continuity.
what is to be done if we have to check continuity over the whole domain of the function?
please help . 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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An area bounded by lines |
2012-12-16 |
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sidra pose la question : find area bounded by functions:
y=x
y=2x
and y=5-x Penny Nom lui répond. |
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A function problem |
2012-11-18 |
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nahla pose la question : f: IN --> IN
n --> f(n)
for every n that belongs the IN : fof(x) = 4n - 3
and for every n that belongs to IN f(2^n) = 2^(n+1) -1
Calculate f(993) Penny Nom lui répond. |
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The derivative of y = sin (30º + x) |
2012-11-07 |
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Saskia pose la question : derivative of y = sin (30º + x) Harley Weston lui répond. |
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Introductory algebra |
2012-10-30 |
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kevon pose la question : if x = 7 is used in the expression 2x + 5 what is the output Penny Nom lui répond. |
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Composition of functions and one to one |
2012-10-17 |
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Ariana pose la question : If f o g are one to one function,does it follow that g is one to one? Give reasons for your answers Penny Nom lui répond. |
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Functions |
2012-09-18 |
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nayeem pose la question : I tried with many functions but I am not getting the exact values please help me
A give an example of a function whose domain equals the set of real numbers and whose range equals the set the set {-1,0,1}?
B Give an example of a function whose domain equals (0,1)and whose range equals [0,1]
C.Give n example of a function whose is the set of positive integers and whose range is the set of positive even integers
D. Give an example of a function whose domain is the set of positive even integers and whose range is the set of positive odd integers
E give an example of function whose domain is the set of integers and whose range is the set of positive integers.
F. Give an example of function whose domain is the set of positive integers and whose range is the set of integers.
please show me the work
Please give me the trick of finding such functions Robert Dawson and Harley Weston lui répond. |
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Functions |
2012-09-18 |
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nayeem pose la question : I tried with many functions but I am not getting the exact values please help me
A give an example of a function whose domain equals the set of real numbers and whose range equals the set the set {-1,0,1}?
B Give an example of a function whose domain equals (0,1)and whose range equals [0,1]
C.Give n example of a function whose is the set of positive integers and whose range is the set of positive even integers
D. Give an example of a function whose domain is the set of positive even integers and whose range is the set of positive odd integers
E give an example of function whose domain is the set of integers and whose range is the set of positive integers.
F. Give an example of function whose domain is the set of positive integers and whose range is the set of integers.
please show me the work
Please give me the trick of finding such functions Robert Dawson and Harley Weston lui répond. |
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The exponential function form f(x)=a^x |
2012-08-13 |
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Lucy pose la question : Hi,
Why does the "a" value in the exponential function form f(x)=a^x have to be negative? Penny Nom lui répond. |
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The range of h(x) = 1/x |
2012-08-11 |
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Lucy pose la question : What is the range of the function: h(x)=1/x (and can you please explain why)? Penny Nom lui répond. |
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A function from {a,b} to {p,q} |
2012-08-10 |
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Lucy pose la question : How can a function relate each element of a set with exactly one element of possibly the same set? Penny Nom lui répond. |
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2 + f(x) and f(x) + 2 |
2011-11-21 |
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Beth pose la question : Do you do y=2+f(x) the same way as if the 2 came after the equation such as y=f(x) +2 when graphing? Penny Nom lui répond. |
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Composition of functions |
2011-09-05 |
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Jenna pose la question : Let f(x)=x^2-1 and g(x)=1-2x. Find the indicated values.
1. f(g(1)) and g(f(1))
Thanks,
Jenna Penny Nom lui répond. |
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tanθ=1.192 |
2011-01-15 |
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Adori pose la question : Use a calculator to approximate two values of the θ (0 ≤θ≤2π) that satisfy the equation.
a) tanθ=1.192
I do not understand how to find the second value of θ. Harley Weston lui répond. |
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f(x) = x + 3 |
2010-05-02 |
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becca pose la question : Find the function value
F(1)if f(x)=x+3 Penny Nom lui répond. |
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Maximizing the area of a rectangle |
2009-12-17 |
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rachel pose la question : A rectangular field is to be enclosed by 400m of fence. What dimensions will give a maximum area? Penny Nom lui répond. |
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y=2x+1 and y=2x-1 |
2009-08-28 |
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MARICELA pose la question : Need help of how to work this problems
y=2x+1 and y=2x-1
First of all what is the difference?
Second I think is easy just to work with the X y with the line in the middle
but how do you get the numbers for each side. Penny Nom lui répond. |
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The integral of a to power x squared |
2009-04-28 |
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JIM pose la question : WHEN I ATTENDED U.OF T. (TORONTO ) MANY YEARS AGO
WE WERE TOLD THE FOLLOWING INTEGRAL COULD NOT BE
SOLVED : a to power x squared . is this still true ?
CURIOUS , JIM Robert Dawson lui répond. |
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The integral of the square root of the sine function |
2009-04-07 |
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Indrajit pose la question : how to integrate this derivative???
∫√sinx Harley Weston lui répond. |
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Trig functions without geometric data |
2009-02-24 |
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bob pose la question : I do not understand how it is possible to find the sine, cosine, or tangent of an angle if
there is no hypotenuse, opposite or adjacent side?! Robert Dawson lui répond. |
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The vertical line test |
2009-01-26 |
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bob pose la question : what is a Vertical line test Stephen La Rocque lui répond. |
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What is f^-1(3) when f(x)=2x-1? |
2009-01-03 |
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Peter pose la question : how do you do functions like f^-1(3) when f(x)=2x-1? Penny Nom lui répond. |
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What is the derivative of (2^sinx)/(logbase4(2x+1))? |
2008-09-16 |
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Jesse pose la question : What is the derivative of (2^sinx)/(logbase4(2x+1)) Harley Weston lui répond. |
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Composition of two functions |
2008-07-04 |
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Kristian pose la question : f(x)= the square of x add to 1 and g(x)=1/x
find: (f o g)x Penny Nom lui répond. |
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The number of hours of daylight |
2008-06-03 |
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Marilyn pose la question : Hi, could you please help me with this question?
In a city (in the Northern Hemisphere) the minimum
number of hours of daylight is 9.6 and the maximum
number is 14.4. If the 80th day of the year (March
21) has 12 hours of daylight, determine a sine
function which gives the number of hours of
daylight for any given day of the year. (Jan 1 = 1,
Jan 2 = 2, etc).
Thank you! Harley Weston 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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Adding rational functions |
2008-04-29 |
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Jonathon pose la question : 1/(x+3) + 1/(x^2+5x+6) = Penny Nom lui répond. |
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Two function problems |
2008-04-10 |
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keith pose la question : find the domain: F(x)= 1/ {ln (x+5) - ln (7-x)}
find the inverse: g(t)= sqrt {2-3 ln (1-t)} Penny Nom lui répond. |
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A function satisfying f(x) + 2f(1/x) = x |
2008-03-25 |
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Joan pose la question : Let f be a function satisfying f(x) + 2f(1/x) =x for all real numbers (x does not equal 0)
a) Find f(1) justify your answer
b) Find f(2) justify your answer Penny Nom lui répond. |
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Composition of functions |
2008-03-07 |
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sharon pose la question : Find FoG(x)
F(x)= the square root of x-9
G(x)= x^2
and also find GoF and their domains Penny Nom lui répond. |
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F( x - 2) = (x + 3)/ (x - 4) |
2007-12-20 |
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Sean pose la question : If F( x - 2) = (x + 3)/ (x - 4) , then F(5) = 10/3
How do you solve this problem and what section of calculus can I learn the technique to solve this type of problem? Stephen La Rocque lui répond. |
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Transformations and compositions |
2007-11-29 |
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mary pose la question : Is there any possible relationship between composite functions and the concept of function transformations? Harley Weston lui répond. |
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Family of functions |
2007-11-12 |
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Russell pose la question : Consider the family of functions
f(t)= Asin3t + Acos3t +Bsin8t + Bcos8t
find exact values of parameters A and B so that f(0) = 2 and f ' (0) = 1 Stephen La Rocque lui répond. |
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Irrational functions |
2007-10-01 |
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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. |
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Relations and functions |
2007-08-16 |
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virginia pose la question : determine whether each relation is a function provide reasons for identifying relation
(3, 4) (5, 9) (9, 9) (2, 3)
(0, 0) (0, 1) (1, 4) (2, 4)
(2, 1) (4, 5) (8, 4) (1, 0)
(8, 3) (8, 0) (7, 7) (4, 7) Steve La Rocque lui répond. |
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Trig functions for angles not between 0 and 90 degrees |
2007-07-16 |
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Tim pose la question : My question: Why is the value of a trigonometric function, the same, for an angle over 90 degrees and its reference angle?
How are the angle and its reference related? Do they both form a triangle that has equal sides? Penny Nom lui répond. |
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Derivative of a Function |
2007-07-09 |
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Bob pose la question : What is the derivative of the function a sub n = [n/(n+1)]^n ? Stephen La Rocque lui répond. |
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Period of a sum of trig functions |
2007-06-17 |
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Aakash pose la question : the period of the function f(x)=cos3x+sin4x+tan4x Stephen La Rocque lui répond. |
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Composition functions |
2007-06-12 |
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Gilligan pose la question : Find functions f and g so that f(g(x)) = H.
(1) H(x) = (1 + x^2)^(3/2)
(2) H(x) = int(x^2 + 1)
I don't know where to start. Stephen La Rocque lui répond. |
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Is the inverse of a function always a function? |
2007-03-29 |
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San pose la question : Is the inverse of a function always a function? Please justify. Thank You! Penny Nom lui répond. |
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y = f(x) and y = 2f(x-6) |
2007-03-02 |
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carl pose la question : if P(4,-5) is a point on the graph of the function y=f(x), find the corresponding point on the graph of y=2f(x-6). Penny Nom lui répond. |
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Composition of functions |
2006-11-19 |
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RJ pose la question : Let f0(x) = 2/2-x and fn+1 = f0 o fn for n greater than or equal to 0. Find a formula for fn and prove it by mathematical induction. Recall that o represents function composition. i.e., (f o g)(x) = f(g(x)). Stephen La Rocque lui répond. |
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Composition of functions |
2006-11-18 |
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Oryan pose la question : Given f(x)=-2x^3 and g(x)-4x-5, find g(f(-1)) Stephen La Rocque lui répond. |
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Piecewise functions |
2006-11-08 |
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Kait pose la question : We discussed how to graph piecewise functions today and I'm very lost!! I'm sitting here staring at this problem that says: f(x){2x+1, if x <1 f(x){-x+4, if x is greater than or equal to 1. Penny Nom lui répond. |
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Piecewise functions |
2006-09-24 |
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Claudia pose la question : hi! i was just looking at a question by someone else about piecewise functions, but i still don't get it.
my problem is
g(x){x+2 if x <-2}
g(x){2x - 1 if x> or = -2} Penny Nom lui répond. |
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The zeros of a function |
2006-06-12 |
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Sky pose la question : find all the real zeros of the function:
f(x)=2x3 + 4x2 - 2x - 4 Stephen La Rocque lui répond. |
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Piecewise functions |
2006-03-21 |
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Kris pose la question : First Problem:
Southeast Electric charges .09 cents per kilowatt-hour for the first 200 kWh.The company charges .11 cents per kilowatt-hour for all electrical usage in excess of 200 kWh. How many kilowatt-hours were used if a monthly electric bill was $57.06? The answer I came up with is 360, is that right? and also how do I set it up in an equation form?
Second Problem:
A construction worker earned $17 per hour for the first 40 hr of work and $25.50 per hour for work in excess of 40 hr. One week she earned $896.75. How much overtime did she work? I came up with 8.5 hrs over-time worked. Again I don't know how to set up the equation to come up with the answer.
I need some pointers on how to figure out story problems! If you have any suggestions that would help me out I would be very grateful. Penny Nom lui répond. |
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sinh(i/2) |
2006-02-09 |
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Louis pose la question : How can you set up an equation to find sinh(i/2) Penny Nom lui répond. |
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fog |
2005-11-12 |
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Janice pose la question : I am having problem with the (fog) function
(fog) (x). Given f(x)= 2x2 ; g(x)= 3-4x 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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Labour efficiency |
2005-08-23 |
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Rob pose la question :
The problem, on the surface, seems very simple and yet has created some controversy among a group of accountants. The problem itself has to do with labour efficiency rates and only involves two variables; standard working hours, and actual working hours. The difficulty lies in deriving an efficiency % from these two numbers.
Standard working hours or the targeted number of labour hours required to produce one widget, which I will represent as "s". Actual working hour or the actual number of labour hours require to produce one widget, which I will represent as "a". Labour efficiency I will represent with "E". The prevailing calculation with which I have a problem with is this:
s/a=E or if s=3000, and a=4000 then 3000/4000=75%
What bothers me about the calculation is that the standard hours get represented as a percentage of the actual hours and in my opinion changes the focus of the calculation from standard or target, where it should be, to the actual hours. I cannot define why, but this just seems inherently wrong to me.
The calculation that I use:
(1+((s-a)/s))=E or if s=3000, and a=4000 then (1+((3000-4000)/3000))=66.67%
My calculation is like a %change from standard calculation. However, there is something that also concerns me about my calculation.
If you substitute 100 for a and 50 for s, then you come to a quandary, because if you plug those numbers into the second equation the result is of course zero % efficient which doesn't sit right with me either. If you plug them into the first calculation you get 50% efficiency which doesn't really seem to work either, because you require 100% more hours to do the same work in this case. ???
Is the first calculation correct? Am I missing something altogether? Are both calculations off base? Harley Weston lui répond. |
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The range of a function |
2005-08-21 |
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Kelsey pose la question : What is the range of the function f(x) = 4x - 6 when the domain is {-3,-1,1,3,5}? Penny Nom lui répond. |
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Rational functions |
2005-04-05 |
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Nicole pose la question : My name is Nicole and I am a teacher at Weyburn Comprehensive School. I am currently teaching both Math B30 and Calculus 30 at the school and I have a question about rational functions. I know that if a rational function (by definition) has common factors in the numerator and the denominator then it is not a rational function (math b30) however in calculus this common factor creates a hole in our graph. Can you explain to me why a common factor or constant does not give us a rational function? Penny Nom and Leeanne Boehm lui répond. |
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Profit |
2005-01-10 |
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Abraham pose la question : The profit a coat manufacturer makes each day is modeled by the equation P(x)=-x2+120x-2000, where P is the profit and x is the price for each coat sold.For what values of x does the company make a profit?
I don 't understand this problem(how to do it) and hope you can help me. Penny Nom lui répond. |
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The points of intersection of two graphs |
2004-11-05 |
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Benjamin pose la question : How do I find the points of intersection of the two functions:
1) y = 2 - e-x
2) y = 1 + x2 Harley Weston lui répond. |
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Limits and composite functions |
2004-08-07 |
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Sue pose la question : I have two questions, one about a limit and the other about a composite function. If you could help me, I'd really appreciate it.
1. Find the limit:
lim[x->0] (x*csc(x))
I converted csc(x) to cos(x)/sin(x), but I didn't know what to do after that.
2. f(g(x)) = ln(x^2 + 4), f(x) = ln(x^2) and g(x) > 0 for all real x, find g(x):
I'm having trouble with this one because x^2 + 4 isn't a perfect square.
--Sue Penny Nom lui répond. |
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The intersection of two graphs |
2004-07-28 |
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JJ pose la question : Is there a way to find the intersections of these graphs algebraically?
x^2 + y = 4 & 2x - y = 1
I got (1.45, 1.9) and (-3.45, -7.9) with a graphing calculator.
AND THESE...
y = 3.29x & y = 5.5(x^0.5)+ 10000
I got x at 3133 with a graphing calculator.
Penny Nom lui répond. |
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Polynomials |
2004-01-25 |
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Bruce pose la question :
A polynomial is defined as
Polynomial functions are functions that have this form:
f(x) = anxn + an-1xn-1 + ... + a1x + a0
The value of n must be an nonnegative integer. That is, it must be
whole number; it is equal to zero or a positive integer.
The coefficients, as they are called, are an, an-1,
..., a1, a0. These
are real numbers.
Questions:
- why must n be positive?
- what are some historical facts
about the evolution of the definition?
Harley Weston lui répond. |
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Finding angles |
2003-12-02 |
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Jason pose la question : I AM TRYING TO SOLVE A TRIG PROBLEM AND HAVE
FORGOT HOW TO DO IT. WHAT I HAVE IS A RIGHT TRIANGLE WITH SIDE A BEING 14
FEET AND SIDE B BEING 3 FEET, USING PYTHAGOREAMS THEOREM SIDE C SHOULD
EQUAL 14.318 FEET ON A RIGHT TRIANGLE BUT I AM TRYING TO REMEMBER HOW TO
FIND MY ANGLES OTHER THAN THE ONE THAT IS 90 DEGREES. Penny Nom lui répond. |
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Graphing a piecewise function |
2003-08-24 |
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Amber pose la question : How do i begin to graph a piecewise function, absolute function or step function? Penny Nom lui répond. |
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Two precalculus problems |
2003-08-04 |
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Kate pose la question :
Please help me verify the identity: cos2x(sec2x-1)=sin2x Also I am having trouble withdetermining whether f(x) is odd, even, or neither f(x)=x3-x Penny Nom lui répond. |
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The domain of 1/g(x) - 5 |
2003-07-03 |
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Barbara pose la question : If the range of g(x) is ( neg. infinity,4] and the domain of g(x) is ( neg. infinity, infinity), how do I find the domain of 1/g(x) - 5? Penny Nom lui répond. |
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y = 1 - sin(x + 60) |
2002-12-10 |
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Eman pose la question : Sketch the graph of y = 1 - sin(x+60). for 0 <= x<= 360, giving the coordinates of the maximum and minimum points and the pints where the curves crosses the y axis. Penny Nom lui répond. |
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Differentiating inverses |
2002-11-20 |
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Amy pose la question : f(x)= x3+x+1, a=1 find g'(a) (g = f -1). I am having trouble finding g(a). Penny Nom lui répond. |
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Functions and relations |
2002-04-25 |
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Erin pose la question : Here's a few math problems that might drive a person insane ;) - If 2f(x) - 3f(1/x) = x^2 what is f(2)?
- What are the domain and range of the following relations?
- x^2 - 4y^2 = 25
- 4x^2 + 9y^2 = 36
- The port of Swan Harbor is 200km away from Merry Town Inlet on a bearing of N50E from Merry Town. A ship leaves Merry Town at 8am and sails N15W at 15 km/h. At the same time, a second ship leaves Swan Harbour on a course of S80W at 20km/hour. How close, to the nearest km, are the two ships at 13:00?
- Prove the identity. 1+sinx + cosx/ 1-sinx + cosx = 1+sinx / cosx
Penny Nom lui répond. |
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Composition of functions |
2002-04-06 |
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Yvonne pose la question : In our new text book, the following question occurs: State the domain and range of g(f(x))given that f(x) = -x2 - 4 and g(x) = sqrt(x) The range of f(x), x<=-4, is the domain of g(x). BUT, there is no solution in the Real numbers for g(f(x))= sqrt(-x2 - 4). In the solutions it says that this is not a function and therefore does not have a domain or range. Is it a relation? Is it anything? Claude Tardif lui répond. |
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Composition of functions |
2001-12-16 |
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Paula pose la question :
- if f(x)= 3x-1 and g(x)= 1/2x + 3 find fog(2)
- find the values of x for which tanx=0
Penny Nom lui répond. |
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Some functions without numbers |
2001-11-16 |
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A student pose la question : I have a worksheet that is about functions. It doesn't only use numbers. I need help to figure out the function and the solution to how the answer is solved. Claude Tardif lui répond. |
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Symmetry of f(x) = ax^n |
2001-10-18 |
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Mohammed pose la question : a function of the form f(x)=axn, where a doesn't equal 0 and n is a positive integer is called a power function . how is the exponent in the equation of a power function related to the symmetry of its graph? Penny Nom lui répond. |
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Inverting a function |
2001-09-30 |
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Brandie pose la question : Could you please tell me what is the basic guideline for inverting a function Example: S(R)=2PiRal V(R)=PiR(squared)bl R(V)=? Claude Tardif lui répond. |
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f(x), f(x) + 2, f(x +2) |
2001-04-04 |
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Monica pose la question : Could you explain to me how one should go about graphing functions such as f(x), f(x+2), and so on. Also, how should you explain things such as constants and relationships among functions? Penny Nom lui répond. |
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Domain and Range and Zeros |
2001-02-27 |
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Beth pose la question : 1. f(x)=15-2x-x2 2. g(t)=square root of 4-t2 3. y=t-3/t2-t-6 Penny Nom lui répond. |
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Adding functions |
2001-02-19 |
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Jackie pose la question : f(x) = x2 + 1; g(x) = x2 - 1 find a) ((f+g) of h)) (x) b) ((f-g) of h)) (x) c) ((f of h) - (g of h)) (x) Penny Nom lui répond. |
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Range of a function |
2000-11-21 |
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David Bell pose la question : Given a rational function such as f(x) = (8x-3)/(4x-1). How can the range be found. Penny Nom lui répond. |
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Graphing F(x) = 3x |
2000-11-06 |
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Jose pose la question : graph the exponential problem F(x)=3x Harley Weston lui répond. |
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Graphing a linear function |
2000-05-17 |
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Chelsea pose la question : I need help with grahing linear functions.If you could e-mail me back the basics and how tos I would be much appriciative. Penny Nom lui répond. |
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sin(7pi/12) |
2000-05-04 |
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Kristel pose la question : What is the exact value of sin 7pi/12? Chris Fisher and Paul Betts lui répond. |
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Functions that satisfy f' = f |
2000-03-16 |
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Kevin Palmer pose la question : Recently my calculus teacher asked his students to try and find any functions whose derivatives where the exact same as the original function. The only function then I have determined that statement to be accurate in is all the natural exponential functions. Ex. f(x) = ex, f'(x) = ex If possible could you please email me all the functions that you can find in which the original function and its derivative is identical. Claude Tardif lui répond. |
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Irrational algebraic functions |
2000-02-21 |
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Bucky Cadena pose la question : Here is the multipart problem: Given f(x) = x-3* squareroot of x + 4 What does the f(x) intercept equal Find the two values for which f(x) = -5 Find the one value for which f(x) = -3 Harley Weston lui répond. |
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Functions |
2000-01-23 |
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Tara pose la question : Hi my name is Tara, I have two math problems that I need help with in my calculus math class. - If f(x)= x - 2 show that (x+3)f(x)-(x+2)f(x+1)+4=0
- Graph this function and use the graph to determine the range y=2x2 - 8x - 3
Harley Weston lui répond. |
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The limit of f(x)/x |
2000-01-22 |
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Laurent Jullien pose la question : I would appreciate help to prove that a twice continuously differentiable convex function from R+ to R has the property that f(x)/x has a limit when x tends to infinity. Claude Tardif lui répond. |
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Functions |
2000-01-06 |
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Tori Morris pose la question : Consider the function f(x)=x2-3. Which of the following are true? - f(1)>f(0)
- f(2)>f(-3)
- f(2)=f(-2)
- f(-1)=f(3).
More than one answer can be true. Penny Nom lui répond. |
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Three algebra problems |
1999-12-28 |
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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)=1/1-x where x is not equal to 0,1. what is f(f(f(a)))?
Harley Weston lui répond. |
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polynomial functions |
1999-11-19 |
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Quinn pose la question :
- Without fully factoring the following show that they all have the same zeros:
I: x4-x2+2x+6 II: -x4+x2-2x-6 III: -4x4+4x2-8x-24 IV: 10x4-10x2+20x+60 - When P(x)=x3-3x2+5x+1 and G(x)=x3-2x2-x+10 are each divided by(x-a) the remainders are equal. At what coordinate point does the graph of P(x) intersect G(x)?
Walter Whiteley lui répond. |
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Inverses of functions |
1999-11-01 |
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Leanne Hickey pose la question : Let f(x) = 2x2 -3x + 2. Find f-1(4) given the fact that f(2) = 4. So the question is finding the inverse of 4, he said it's easier than it looks. Penny Nom lui répond. |
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Piecewise functions. |
1999-10-20 |
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Jenny pose la question : How do you figure out a piecewise function by hand? e.x. ( 2x (if x is not equal to 0) f(x)=< ( 0 (if x is not equal to 0) Harley Weston lui répond. |
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Even and Odd Function |
1999-06-17 |
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Kent pose la question : There is one function with the domain of all real numbers that is both even and odd. Please give me the answer to this question before I go insane. Penny Nom lui répond. |
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Points on a Graph |
1998-10-03 |
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Nouver Cheung pose la question : If the point P(-3,2) is on the graph of y=f(2x-1), what point must be on y=f(x)-3? Harley Weston lui répond. |
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Polynomials |
1998-01-13 |
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Sarah Storkey pose la question : Hi, My name is Sarah, My question is at the junior level. My question is, what is a polynomial? Harley Weston lui répond. |
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Square Roots and Functions. |
1997-04-23 |
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Ed pose la question : 1. In most texts the solution to a question such as square root x = -6 is x is undefined. Yet when teaching to solve xsquared = 36 x = +6 or -6 There appears to be a contradiction here. My question is when, where and why do we use the principle square root, not both + and -? This often occurs as the extraneous root in the solution of radical equations and in stating the domain and range of functions involving square roots. 2. Are there any simple rules for determining whether equations are functions without graphing them and doing a vertical line test? Harley Weston lui répond. |
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