Question

What is the inverse of the function below?

f(x) = 11x + 9

f -1(x) = -11x - 9

f -1(x) = x - 9

11

f -1(x) = x - 11

9

f -1(x) = 9 + 11x

Answer 1

take
y = 11x +9
solve it for x
11x = y -9
x = y/11 - 9/11
now switch y an x
y = x/11 - 9/11
it's the inverse function u need

f^-1(x) = x/11 -9/11
\[f^{(-1)}(x) = \frac{ x-9 }{ 11 }\]

got it :) ?

Answer 2

sorta lol