Question

If F(x)=2x/7+4, which of the following of the inverse of F(x)?

A. F-1(x)= 2(x-4)/7
B. F-1(x)= 7(x+4)/2
C. F-1(x)= 2(x+4)7
D. F-1(x)= 7(x-4)/2

Please explain how you got the answer

Answer 1

Hello,

Answer D

y=2x/7+4
x=2y/7+4
(x-4)*7/2=y

Answer 2

Option D is correct.

Explanation:

Given : function f(x) =
`(2x)/(7)+4`

We have to find inverse function of f(x)

Le, y be any arbitrary image of f(x).

So, y = f(x)

`y=(2x)/(7)+4`

`y-4=(2x)/(7)`

`7*(y-4)=2x`

`x=(7(y-4))/(2)`

So, Inverse of f(x) is
`f^(-1)(x)=(7(x-4))/(2)`

Therefore, Option D is correct.