Question

If f (x) =1/9x-2 what is f1(x)?

Answer 1

Answer:

$\large\boxed{f^{-1}(x)=9x+18}$

Step-by-step explanation:

$f(x)=\dfrac{1}{9}x-2\to y=\dfrac{1}{9}x-2\\\\\text{Exchange x to y and vice versa}\\\\x=\dfrac{1}{9}y-2\\\\\text{solve for}\ y:\\\\\dfrac{1}{9}y-2=x\qquad\text{add 2 to both sides}\\\\\dfrac{1}{9}y=x+2\qquad\text{multiply both sides by 9}\\\\9\!\!\!\!\diagup^1\cdot\dfrac{1}{9\!\!\!\!\diagup_1}y=9x+(9)(2)\\\\y=9x+18$