SOLUTION: Please help me find g•f and then find f(g(-2)) Using f(x)=2x+3 and g(x)=x^2-4

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Question 1165164: Please help me find g•f and then find f(g(-2))
Using f(x)=2x+3 and g(x)=x^2-4
Found 2 solutions by Seutip, josgarithmetic:
Answer by Seutip(231) About Me  (Show Source):
You can put this solution on YOUR website!
Find: g(f) and f(g(-2))
Using f(x)=2x+3 and g(x)=x^2-4
First solve g(-2) it means find g when x=-2
g%28x%29=x%5E2-4
g%28-2%29=%28-2%29%5E2-4
g(-2) = 0
Then solve f(g(-2)) or f(0) it means find f when g(-2)=0
f%28x%29=2x%2B3
f%280%29=2%280%29%2B3
f(g(-2)) = 3
Then solve g•f it means g of f g(f)
since f=3
g%283%29+=3%5E2-4
g•f = 5

HOPE IT HELPS!

Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
%282x%2B3%29%28x%5E2-4%29
2x%5E3%2B3x%5E2-8x-12




AND THE OTHER


2%28x%5E2-4%29%2B3
subthe-2
2%28%28-2%29%5E2-4%29%2B3
2%280%29%2B3
3