SOLUTION: I seemed to have made an error in getting the right answer for this problem. Can you help with the right answer? thanks! Find the inverse function of f. f(x)=1/(-8 x^2 - 8

Algebra ->  Equations -> SOLUTION: I seemed to have made an error in getting the right answer for this problem. Can you help with the right answer? thanks! Find the inverse function of f. f(x)=1/(-8 x^2 - 8      Log On


   

Question 198355: I seemed to have made an error in getting the right answer for this problem. Can you help with the right answer?
thanks!
Find the inverse function of f.
f(x)=1/(-8 x^2 - 8),x>=0
Answer by arallie(162) About Me  (Show Source):
You can put this solution on YOUR website!
f%28x%29=1%2F%28-8x%5E2-8%29x%3E=0
f%5E-1%28x%29=?
y=1%2F%28-8x%5E2-8%29
Invert
x=1%2F%28-8y%5E2-8%29
Solve for y
x%28-8y%5E2-8%29=1
-8y%5E2-8=x%5E-1
-8y%5E2=x%5E-1%2B8
y%5E2=-%28x%5E-1%2B8%29%2F8
y=sqrt%28-%28x%5E-1%2B8%29%2F8%29
So
If f%28x%29=1%2F%28-8x%5E2-8%29x%3E=0
Then f%5E-1%28x%29=sqrt%28-%28x%5E-1%2B8%29%2F8%29inf%3E=x%3E=-inf
Or f%5E-1%28x%29=sqrt%281-%281%2F8x%29%29inf%3E=x%3E=-inf