SOLUTION: Find g•f f(x)=2x+3 g(x)=x^2-4

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Question 1165144: Find g•f
f(x)=2x+3
g(x)=x^2-4

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
here put the 2x+3 into the g(x) function anywhere there is an x
g o f= (2x+3)^2-4
f(x)=2x
g(x)=x^2
f o g (x) is where the x^2 from g is substituted for x in f so f o g (x)=2x^2
g o f(x) is where the 2x in f is substituted for thee x in g and that is (2x)^2=4x^2.
so in the above g o f(x) is putting the 2x+3 from f into the x in g
that makes the answer (2x+3)^2-4. The constants don't change in any instance.