Question

Find the inverse of the function f(x) = 2x - 4

Answer 1

The correct answer is f^-1(x)=1/2x+2.

1. Substitute y for f(x). ( y=2x+4 )

2. Interchange the variables x and y. ( x=2y-4 )

3. Swap the sides. ( 2y-4=x )

4. Move the constant to the right. ( 2y=x+4 )

5. Divide both sides by 2. ( y=1/2x+2 )

6. Use substitution to substitute f^-1(x) for y.

Thus the inverse is f^-1(x)=1/2x+2