Trouble with even and odd functions: interval 9 to -9 (f(x) +g(x)) dx

calc67x

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I have this question:

If f is an odd function and g is an even function, please find the value of the following

interval 9 to -9 (f(x) +g(x)) dx.

Now I know that if f is odd then that f(x) would be zero.
For the even function it is 2 interval 9 - 0. I am not sure how to evaluate this since there are no actual numbers to plug in.
If the problem just had x then the antiderivative would be x^2/2 but we only have f(x) here.
The book indicates that the answer is 22. If so, are we adding 9+2 and then multiplying by 2? If so, why?
I'm trying hard to get it.
 

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I would say that without any information concerning \(\displaystyle g(x)\) other than that it is an even function, we cannot obtain a numeric value for the given definite integral.
 
I have this question:

If f is an odd function and g is an even function, please find the value of the following

interval 9 to -9 (f(x) +g(x)) dx.

Now I know that if f is odd then that f(x) would be zero.
For the even function it is 2 interval 9 - 0. I am not sure how to evaluate this since there are no actual numbers to plug in.
If the problem just had x then the antiderivative would be x^2/2 but we only have f(x) here.
The book indicates that the answer is 22. If so, are we adding 9+2 and then multiplying by 2? If so, why?
I'm trying hard to get it.
There are other ways to get 22, then 2(9+2)!!!. The only way the answer is 22 is if you are told that the integral of g(x) from 0 to 9 is 11 OR the integral of g(x) from -9 to 9 is 22 OR you are given the exactly what g(x) is and it works out to 22. As MarkFL said, you are not given enough information.
 
Is it possible that there is additional information elsewhere than what you quoted -- perhaps in the instructions for a group of exercises, or in a picture?

Or could you have looked at the answer to the wrong question?
 
Thanks, All!

This was an easy question - but there was information that was almost cut off on the sheet and I missed it.
I don't feel secure with the Calculus yet so sometimes I am not sure what I'm looking for.
Thanks for all your efforts in trying to assist though!
 
This was an easy question - but there was information that was almost cut off on the sheet and I missed it.
I don't feel secure with the Calculus yet so sometimes I am not sure what I'm looking for.
Thanks for all your efforts in trying to assist though!

Just for the sake of closure (for anyone who's been following this), could you tell us what the whole problem was?
 
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