Question

If fx)=1/9x-2, what is f¹(x)?

0 f¹(x)= 9x + 18
0 f¹(x)= 1/9x+ 2
0 f¹(x)= 9x+2
0 f¹(x)= -2x + 1/9

Answer 1

f⁻¹(x)= 9x + 18

Explanation:

1. Replace f(x) with x, and x with y: x=1/9y-2

2. Solve for y:

x=1/9y-2

9x=y-18

9x+18=y

3. Replace y in step 2 with f⁻¹(x)