Question

If f(x) and 1

are inverse functions of each other and f(x) = 2x+5, what is
1 (8)?
Ο
7 η/υ
Ο
Ο
Glo
Ο

Answer 1

Explanation:

let f(x)=y

y=2x+5

flip x and y

x=2y+5

2y=x-5

y=(x-5)/2

f^{_1}(x)=(x-5)/2

but f^{-1}(x)=1

so (x-5)/2=1

x-5=2

x=2+5=7