







The composition of a function with itself 
20160717 

Mel pose la question : If f(1 + 3x) = 1 * x, solve f(f(x)) Penny Nom lui répond. 





A stone is dropped in a lake 
20150214 

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. 





The continuity of f(x,y)=ln(x^2+y^2) 
20130217 

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. 





A function problem 
20121118 

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. 





Composition of functions and one to one 
20121017 

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. 





Limits and composition 
20111230 

Rahul pose la question : I want to know about limit proofs of composite functions. Like limit of log of a function equals log of limit of the function Penny Nom lui répond. 





The LCM of 6,15 and x is 90 
20111030 

Richie pose la question : Hi there,
There are 2 parts to the question.
#1. Factorise 90. This is easy, 90=2x3x3x5
#2
LCM of 6,15 and x is 90. What are possible values of x if x is odd?
From #1, since 90=6x15, how can this be used to work out possible values of x?
Thanks in advance,
Richie Penny Nom lui répond. 





Composition of functions 
20110905 

Jenna pose la question : Let f(x)=x^21 and g(x)=12x. Find the indicated values.
1. f(g(1)) and g(f(1))
Thanks,
Jenna Penny Nom lui répond. 





Composition of two functions 
20080704 

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. 





Composition of functions: feet, inches and yards 
20080405 

Coya pose la question : write a function f(x) that converts feet to inches.Now write a function g(x) that converts yards to feet. Explain what the composite function f(g(x)) means. Then evaluate f(g(x)) for x = 3,6, and 9. Stephen La Rocque lui répond. 





Composition of functions 
20080307 

sharon pose la question : Find FoG(x)
F(x)= the square root of x9
G(x)= x^2
and also find GoF and their domains Penny Nom lui répond. 





Transformations and compositions 
20071129 

mary pose la question : Is there any possible relationship between composite functions and the concept of function transformations? Harley Weston lui répond. 





Derivative of a Function 
20070709 

Bob pose la question : What is the derivative of the function a sub n = [n/(n+1)]^n ? Stephen La Rocque lui répond. 





The composition of functions 
20070614 

Gilligan pose la question : Question from Gilligan, a student:
Let f(x) = x^2, g(x) = 3x and h(x) = (sqrt{x}) + 1. Express each function as a composite of f, g and/or h.
(1) p(x) = 3(sqrt{x}) + 3
(2) Q(x) = (sqrt(sqrt{x}) + 1}) + 1 Penny Nom lui répond. 





Composition functions 
20070612 

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. 





Factoring a trinomial 
20070327 

Kim pose la question : Hi, could you please help me solve this.
3x(squared) +20x  7 Leeanne Boehm lui répond. 





solve; 
20061128 

Monique pose la question : solve; f(f(x)) = 2x + 4 ; if f(x) = 1 Penny Nom lui répond. 





Composition of functions 
20061119 

RJ pose la question : Let f0(x) = 2/2x 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. 





Composition of functions 
20061118 

Oryan pose la question : Given f(x)=2x^3 and g(x)4x5, find g(f(1)) Stephen La Rocque lui répond. 





fog 
20051112 

Janice pose la question : I am having problem with the (fog) function
(fog) (x). Given f(x)= 2x^{2} ; g(x)= 34x Penny Nom lui répond. 





Limits and composite functions 
20040807 

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. 





Making a square 
20030907 

A student pose la question : if I am given any number (say 80 for example), how may I determine the smallest whole number integer which when multipled by it will yield a square number ? In other words if I express this as: 80Ý*ÝnÝ=ÝsquareÝnumber, what is the least value of n which will yield a square. Penny Nom lui répond. 





Composition of functions 
20020406 

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) = x^{2}  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(x^{2}  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. 





Composition of functions 
20011216 

Paula pose la question :
 if f(x)= 3x1 and g(x)= 1/2x + 3 find fog(2)
 find the values of x for which tanx=0
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. 

