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Math - Questions and Answers from our Archives  Is the Inverse a
Function?  Date: 9/2/96 at 16:16:17 From: Ralph Senter Subject:
Compositions and Inverses of Functions  I am lost on how to do
these problems. Can you help me?  Find the  inverse of each
function. Then state whether the inverse is a   1. f(x) = 4x+4
2. f(x) = x(cubed)         3. f(x) = x(squared)-9  Date: 9/3/96
at 3:32:47 From: Doctor Mike Subject: Re: Compositions and
Inverses of Functions  Hello Ralph, 1. If a function f takes x
to some expression in x, then the inverse  has to "undo" what
was done by f.  In this case it's pretty easy.   f starts with
x, multiplies it by 4, and then adds 4. To reverse that  process
you subtract 4, and then divide by 4.    Often the inverse of a
function f is written as f with a "-1"  superscript, but for
typing here I'm going to use "i" for it.   Then we have :
x - 4         i(x)  =  -------  As a final check, it must be
true th