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Math Help - integration

  1. #1
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    integration

    I have tried this problem a million times, and many different ways, and I can't seem to figure out the right answer. Please help!! Thank you so much!

    I have to solve:
    integral from (-1) to (1) (lower limit -1 and upper limit 1) of the function: pi*((x^3)+1)^2.

    I've integration by parts, I tried multiplying it out and doing it that way, and I get answers in all the ways I do it but I never get the same answer, and none of the answers I've gotten have been right.
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  2. #2
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    Quote Originally Posted by amaya View Post
    I have to solve:
    integral from (-1) to (1) (lower limit -1 and upper limit 1) of the function: pi*((x^3)+1)^2.
    Only actually concerns us \int_{ - 1}^1 {\left( {x^3  + 1} \right)^2 } .

    Now just expand.
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  3. #3
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    Same problem: integration

    Concerning my last problem:
    integral from -1 to 1 of ((x^3)+1)^2

    I expanded....and I solved it and I got 2pi. But that's the incorrect answer...I don't know where I went wrong. help?
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  4. #4
    Math Engineering Student
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    Show your work, since such answer is incorrect. (May be you're messing with some calculation there.)
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  5. #5
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    integration

    I went through my work once again and I figured out where I went wrong. I got (16/7)pi and summited into the computer and finally got the right answer. Thanks a lot!
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