Question

How do you find the inverse of `f(x)=2x+3` and is it a function?

Answer 1

`f^-1 x = 1/2(x - 3 )`

Explanation:

Basically this is an exercise in changing the subject of an expression. Given y in terms of x , the inverse is to express x in terms of y.

let y = 2x + 3 - now change the subject to x.

hence : 2x = y - 3 → `x = 1/2(y - 3 )`

It is usual to write the inverse in terms of x.

`rArr f^-1 x = 1/2(x - 3)`

This is the equation of a line and is a function