How do i use composition of functions to determine whether the functions in each pair are inverse functions?

y=2x-3 and y=2x+3

1 Answer
Nov 27, 2017

f(g(x)) does not equal x, so the functions are not inverses.

Explanation:

This is how to figure this out:

Write #y=2x-3# as #f(x)=2x-3#, and write #y=2x+3# as:
#g(x)=2x+3#

Determine:
#f(g(x))= 2(2x+3)-3#
#=4x+3#

So, since f(g(x)) doesn't equal x, the functions are not inverses!

Hope this helps!