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Homework Help: Integral of cos(8x^2)? multivariable calc

  1. Feb 23, 2012 #1
    Integral of cos(8x^2)??? multivariable calc

    1. The problem statement, all variables and given/known data

    dA1w3.png

    2. Relevant equations

    none

    3. The attempt at a solution

    So i reversed the order...

    jZ4n0.png

    and couldn't figure out how to integrate cos(8x^2). I looked at my trig identities, tried on my graphing calc, and even wolfram alpha gave me a strange answer that i cant use.

    Either i'm doing something wrong, or missing something obvious.

    Thanks
    Jake
     
  2. jcsd
  3. Feb 23, 2012 #2
    Re: Integral of cos(8x^2)??? multivariable calc

    ...dy dx?
     
  4. Feb 23, 2012 #3
    Re: Integral of cos(8x^2)??? multivariable calc

    oh yeah. in my work i should have wrote dydx instead of dxdy good catch. wow. maybe i can solve it now.

    lets see...


    wow... the answer was 0, after a page of work and a few hours of confusion
     
    Last edited: Feb 23, 2012
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