SOLUTION: Please I need help on: The Functions f(x)=x+2 , g(x)=-3x Calculating this composition... g(f(2)) I have tried (-3x(x+2))(2) and got the answer of -12x but since I am not s

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Question 353722: Please I need help on: The Functions f(x)=x+2 , g(x)=-3x Calculating this composition...
g(f(2))
I have tried (-3x(x+2))(2) and got the answer of -12x but since I am not sure on how to solve this problem i would appreciate your help on this.
-Thank you so much for your time.

Found 2 solutions by stanbon, jim_thompson5910:
Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
Functions f(x)=x+2 , g(x)=-3x
Calculate this composition...
g(f(2)) = g[2+2] = g[4] = -3*4 = -12
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Cheers,
Stan H.

Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!
You should get a number (not an algebraic expression) as an answer


First, calculate the inner function f(2)


So (plug in x=2 into f(x)), which gives us


So this means that since


So from here, plug x=4 into g(x) to get


So


and equivalently


If you need more help, email me at jim_thompson5910@hotmail.com

Also, feel free to check out my tutoring website

Jim

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