Question

If f(x)=5x-1, then f^-1(x)=

Answer 1

f^-1(x) = (x+1)/5

Explanation:

f(x)=5x-1

y = 5x-1

Exchange x and y

x = 5y-1

Solve for y

Add 1 to each side

x+1 = 5y-1+1

x+1 = 5y

Divide by 5

(x+1)/5 = 5y/5

(x+1)/5 = y

The inverse is (x+1)/5

f^-1(x) = (x+1)/5