How do you find [fog](x)[fog](x) and [gof](x)[gof](x) given f(x)=1/2x-7f(x)=12x7 and g(x)=x+6g(x)=x+6?

1 Answer
Mar 7, 2017

The answers are [fog] (x) =1/2x-4[fog](x)=12x4 and [gof] (x)=1/2x-1[gof](x)=12x1

Explanation:

This is a composition of functions

f(x)=1/2x-7f(x)=12x7

g(x)=x+6g(x)=x+6

[fog] (x) =f(g(x))=f(x+6)=1/2(x+6)-7[fog](x)=f(g(x))=f(x+6)=12(x+6)7

=1/2x+3-7=1/2x-4=12x+37=12x4

[gof] (x)=g(f(x))=g(1/2x-7)= 1/2x-7+6[gof](x)=g(f(x))=g(12x7)=12x7+6

=1/2x-1=12x1