Question

What is the inverse of the function f(x) = one-quarterx – 12?

Answer 1

f-1(x) = 4x + 48.

Explanation:

let f(x) = y = 1/4 x - 12

We solve for x:

y = 1/4 x - 12

1/4 x = y +12

Multiply through by 4:

x = 4y + 48

The inverse f-1(x) = 4x + 48.

Answer 2

f^(-1)(x) = 4x + 48.

Explanation:

Is suppose the function is f(x) = 1/4 x - 12

This is equivalent to the line y = 1/4 x - 12.

To get the inverse, change the x and y:

x = 1/4 y - 12

Now solve for y:

x + 12 = 1/4 y

y = 4x + 48

So the inverse f^(-1)(x) = 4x + 48.