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Math Help - Integration

  1. #1
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    Integration

    Please tell me where I went wrong.



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    Quote Originally Posted by r_maths View Post
    Please tell me where I went wrong.



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    For starters your terminology, um..., stinks. You still have an integral sign AFTER you integrated!! I don't have the fancy fonts, but let me rewrite this.

    Iave = 1/(1/300 - 0)*Int[2*sin(600t) dt, 0, 1/300]

    = 300*2*Int[sin(600t) dt, 0, 1/300]

    Let x = 600t ==> dx = 600 dt

    Iave = 300*2*Int[sin(x) * (dx/600), 0, 2] <-- Watch your limits of integration!

    = Int[sin(x) dx, 0 ,2]

    = -cos(2) + cos(0)

    = 1 - cos(2) = 1.41615 A

    (Your given answer of 0.46 A is incorrect.)

    -Dan
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    I'll trust you over the book.
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    Forum Admin topsquark's Avatar
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    Quote Originally Posted by r_maths View Post
    Thanks

    I'll trust you over the book.
    I trust my calculator over the book, too.

    (Of course, please check my work. I've been wrong before!)

    -Dan
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