Question

Which of the following is the function F(x) if F^-1(y)=y/8 + 3 ?

A.) F(x)=8x+3

B.) F(x)=8(x-3)

C.) F(x)=8x-3

D.) F(x)=8(x+3)

Answer 1

Inverse function is y/8 + 3.

F^-1(y)=y/8 + 3.

Change  F^-1(y)  to x

x = y/8 + 3

Now solve for y.

Subtract 3 from each side.

x - 3 =y/8

Multiply each side by 8.

y = (x - 3)8

Change y to f(x) .

f(x) = 8(x - 3)

So option B is correct.