Question

Which equation is the inverse of y = 9x2 – 4?

Answer 1

y = +/- [√x+4) ] / 3

Explanation:

1) To find the inverse of the function y = 9x^2 - 4, exhange the variables x and y, and then solve for the new y.

2) Exchange of the variables: y = 9x^2 - 4 → x = 9y^2 - 4

3) Solve for y:

9y^2 = x + 4

y^2 = [x + 4] / 9

y = +/- [ √ (x + 4) ] / 3