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25 articles trouvés pour ce sujet.
The composition of a function with itself 2016-07-17
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 2015-02-14
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) 2013-02-17
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 2012-11-18
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 2012-10-17
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 2011-12-30
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 2011-10-30
Richie pose la question :
Hi there,
There are 2 parts to the question.
#1. Factorise 90. This is easy, 90=2x3x3x5

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 2011-09-05
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))


Penny Nom lui répond.
Composition of two functions 2008-07-04
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 2008-04-05
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 2008-03-07
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.
Transformations and compositions 2007-11-29
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 2007-07-09
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 2007-06-14
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 2007-06-12
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 2007-03-27
Kim pose la question :
Hi, could you please help me solve this.

3x(squared) +20x - 7

Leeanne Boehm lui répond.
solve; 2006-11-28
Monique pose la question :
solve; f(f(x)) = 2x + 4 ; if f(x) = 1
Penny Nom lui répond.
Composition of functions 2006-11-19
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.
Composition of functions 2006-11-18
Oryan pose la question :
Given f(x)=-2x^3 and g(x)-4x-5, find g(f(-1))
Stephen La Rocque lui répond.
fog 2005-11-12
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.
Limits and composite functions 2004-08-07
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.


Penny Nom lui répond.
Making a square 2003-09-07
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 2002-04-06
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.
Composition of functions 2001-12-16
Paula pose la question :
  1. if f(x)= 3x-1 and g(x)= 1/2x + 3 find fog(2)

  2. find the values of x for which tanx=0

Penny Nom lui répond.
LOG(LN(x)) = 1 2000-07-28
An algebra student pose la question :
LET F(x)=LOG X AND G(x)= LN X. SOLVE (f *G)(x)= 1

Harley Weston lui répond.



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