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Math Help - Integration of trigs

  1. #1
    Junior Member Misa-Campo's Avatar
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    Integration of trigs



    sorry if you cant see but its between pie/2 and 0, thanks.
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  2. #2
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    Quote Originally Posted by Misa-Campo View Post


    sorry if you cant see but its between pie/2 and 0, thanks.
    Double angle formula: \cos(2 \theta) = 1 - 2 \sin^2 \theta.

    In your problem, \theta = 2x \Rightarrow \sin^2 (2x) = \, .......
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  3. #3
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    Hello, Misa-Campo!

    \int^{\frac{\pi}{2}}_0 \sin^2(2x)\,dx

    Use the identity: . \sin^2\!\theta \:=\:\frac{1 - \cos2\theta}{2}

    And we have: . \int^{\frac{\pi}{2}}_0 \sin^2(2x)\,dx \;=\;\frac{1}{2}\int^{\frac{\pi}{2}}_0(1 - \cos 4x)\,dx

    . . Got it?

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  4. #4
    Junior Member Misa-Campo's Avatar
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    Thx alot guys
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