SOLUTION: I am not understanding these Adavanced Functions and could use some help please. f(x)=-3x-3 and g(x)=x^2+2x find (f-g)(2)

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Question 533206: I am not understanding these Adavanced Functions and could use some help please.
f(x)=-3x-3 and g(x)=x^2+2x find (f-g)(2)
Found 2 solutions by stanbon, KMST:
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
I am not understanding these Adavanced Functions and could use some help please.
f(x)=-3x-3 and g(x)=x^2+2x find
(f-g)(2) = f(2)-g(2)
= [-3*2-3]-[2^2+2*2]
= -9-0
= -9
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Cheers,
Stan H.
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Answer by KMST(5328) (Show Source):
You can put this solution on YOUR website!
(f-g)(x)=f(x)-g(x) for all x.
For x=2 (f-g)(2)=f(2)-g(2)
You have 2 options to solve your problem:
Option 1 _ You can first work with the x in the functions as they are written to generate the general expression for (f-g)(x), and substitute x=2 later.
Option 2 _ You can calculate f(2) and g(2) first and then do the subtraction with the two numbers.
All that's said above works similarly for (f+g), (fxg) and (f/g)
Sometimes one option is easier or more convenient than the other.
In your case:
Option 1

Option 2