Question

Find the inverse of the function.
y = 2x²-4

Answer 1

Below in bold.

Explanation:

y = 2x²-4

First find x in terms of y:

2x² = y - 4

x² = (y - 4)/2

x = √ [(y - 4)/2]

Now replace x by the inverse f-1(x) and y by x:

f-1(x) = √ [(x - 4)/2] (Note: it's the positive square root only)