inverses of equations

Question

find the inverse of f(X)= 4sqrt(x-2)-8

Answer 1

Sarah, 

 

1. set f(x)=y

2. solve y=4*(x-2)^1/2-8 for x in terms of y, I got x=(1/16)*(y²+16y+96)

3. substitute x for y giving f^-1(x)= (1/16)*(x²+16x+96)

4. You can check the answer by using the definition of the inverse i.e. f(f^-1(x))=x

 

Hope this helps you

 

Jim