## Combinations and Compositions of Functions: confused with Q

Quadratic equations and inequalities, variation equations, function notation, systems of equations, etc.
pbro
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Joined: Thu Apr 12, 2012 9:55 am
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### Combinations and Compositions of Functions: confused with Q

Hi
There's a question in my book which I am confused with. I have gone through my textbook and haven't found similar example questions and am hoping someone can set me off in the right direction.

The Question:
If f(2)=0, g(2)=8, and h(2)=-1, then calculate the value of the following functions at x=2.
a) (3f+4g) (2)

Do they mean that f(2)=0 is at x=2 and we just substitute the f into the question? I couldn't think of anything else but I'm almost definitely sure that that's wrong. Where does the x=2 come into play?

cheers
confused

maggiemagnet
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### Re: Combinations and Compositions of Functions: confused wit

If f(2)=0, g(2)=8, and h(2)=-1, then calculate the value of the following functions at x=2.
a) (3f+4g) (2)

Do they mean that f(2)=0 is at x=2 and we just substitute the f into the question?
Yes. They're using something called "function notation". You can learn what that is and how to use it in this lesson.

In the same way, by "g(2)=8", they mean that g(x) = 8 when x = 2, so plug that into the equation, too.

pbro
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Joined: Thu Apr 12, 2012 9:55 am
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### Re: Combinations and Compositions of Functions: confused wit

Thanks for the quick reply. It just seemed too easy for me as the stuff we did before was at a higher level. I'll def go through your link though.
Thanks again!