ANSWER
F⁻¹(x) = 6(x - 3)
Step-by-step explanation
To find the inverse function we have to clear x as a function of f. In this function

the first step is to subtract 3 from both sides of the equation:

And then multiply both sides by 6:

Finally change the names of x and F(x). x is now F⁻¹(x) and F(x) is now x:
