Does f(g(x)) = g(f(x))?

[nycmathguy]

Section 1.8
Question 65

See attachment.

Let me find f(g(x)).

f(g(x)) = plug 6x into f(x).

So, f(g(x)) = 6x + 1.

I now find g(f(x)).

g(f(x)) = plug (x + 1) into 6x.

g(f(x)) = 6(x + 1) = 6x + 6.

I conclude that f(g(x)) does not equal g(f(x)).

You say?

 

[MathLover1]

correct

 

[nycmathguy]

correct

This is a bit easy.