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Math Help - Integral

  1. #1
    Junior Member
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    Integral

    Evaluate \int_0^\infty\frac{2-2\cos x}{xe^x}\,dx
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  2. #2
    Math Engineering Student
    Krizalid's Avatar
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    Introduce the following parameter

    \frac{1-\cos x}x=\int_0^1\sin(ux)\,du, then construct a double integral and switch the order of integration.

    The answer is \ln2.
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