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Math Help - Trig integrals

  1. #1
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    Trig integrals





    so i tried the problem

    got ln(sec(4x)) & -2cos(4x)



    what am i doing wrong?
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  2. #2
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    tried what problem?
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  3. #3
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    Quote Originally Posted by artvandalay11 View Post
    tried what problem?

    the y = is the actual question.
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  4. #4
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    Quote Originally Posted by XplicitZero View Post
    the y = is the actual question.
    you need to know when tan(4x)=2sin(4x)?
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  5. #5
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    No, the OP trying to integrate each function between the limits \left(-\frac{\pi}{2}, \frac{\pi}{2}\right).
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  6. #6
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    Quote Originally Posted by XplicitZero View Post




    so i tried the problem

    got ln(sec(4x)) & -2cos(4x)



    what am i doing wrong?
    both odd functions with limits of integration from -a to a ... what's that tell you?
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  7. #7
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    don't know =(
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  8. #8
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    Quote Originally Posted by XplicitZero View Post
    don't know =(
    visualize the definite integral ... graph one of them and see for yourself.
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  9. #9
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    the graph looks crazy. line + zig-zag, but i really dunno.
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  10. #10
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    window is from \left[-\frac{\pi}{12} \, , \, \frac{\pi}{12}\right]

    look at it ... what's the value of the definite integral?
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