Question 549654
a) f(x)= -3x ,g(x)=2x+6


f(g(x)) is just basically saying everywhere you have an x in f(x), put the entire g(x) function.

So for this example, f(g(x))=-3(2x+6)

and g(f(x)) is just saying everywhere you have and x in g(x), put the entire f(x) function

So for this example, g(f(x))=2(-3x)+6

I will let you do b) yourself (hint: VERY similar to a), just different functions.


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Hopefully this helps!  Let me know if you are still unsure 
Romans 5:8