Question

Select the correct answer.

Answer 1

Answer:

D. inverse of f(x) = $\frac{9x - 99}{10}$

Step-by-step explanation:

I. Given f(x) = y

  y = $\frac{10}{9x} + 11$

II. Switch x to y and y to x

  x = $\frac{10}{9y} + 11$

   x - 11 = 10/9y

   $\frac{x - 11}{\frac{10}{9} }$ = y

   x - 11 ($\frac{9}{10}$) = y

   [(x - 11)9] / 10 = y

   (9x - 99) /10 = y

So y or f(x inverse) = $\frac{9x - 99}{10}$

Hope that help :)

Answer 2

Step-by-step explanation:

let f(x) be y

∴ y = 10x/9 +11

(y - 11 )× 9/ 10 = x

Interchange x->y and y->x

(x - 11)×9/10 = y

here y is your f⁻¹(x)

∴ f⁻¹(x) = (x - 11 )× 9/10

or, f⁻¹(x) = 9x/10 - 99/10

Option (D) is correct