SOLUTION: determine f-1 for f(x) = cubed root of(x+5) (in f -1) is not f minus 1 or the negative 1 power of f)

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Question 4939: determine f-1 for f(x) = cubed root of(x+5)
(in f -1) is not f minus 1 or the negative 1 power of f)
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
By f%5E%28-1%29%28x%29+=+cuberoot+%28x%2B5%29+ you refer to the inverse of the function f(x). Am I right?

Given y = cuberoot (x+5)
My approach to finding an inverse of f(x) is two steps.

Step 1. Interchange the x and y.
x= cuberoot (y+5)

Step 2. Solve for y.
To undo the cuberoot, you must cube both sides:
x%5E3+=+y%2B5+

Next, undo the +5 by subtracting 5 from each side:
x%5E3+-+5+=+y

This new y that you just solved for the the inverse function for f(x)

The inverse function for f%28X%29+=+cuberoot+of+%28x%2B5%29+ is f%5E%28-1%29+%28x%29+=+x%5E3+-+5+

R^2 at SCC