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Math Help - [SOLVED] What integration technique to use?

  1. #1
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    [SOLVED] What integration technique to use?

    Substitution, trig, or partial fractions do not work.
    I have tried integration by parts and all it does is give me either a cos(3x) or back to a sin(3x).
    Here is the problem...
    Integrate (e^(2x))sin(3x) dx

    I can't think of another way around it.
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  2. #2
    Behold, the power of SARDINES!
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    look at post #3 in this thread to see the idea for the integral

    It is integration by parts twice

    http://www.mathhelpforum.com/math-he...ion-parts.html
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  3. #3
    MHF Contributor matheagle's Avatar
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    You integrate this by parts twice.
    It doesn't matter which you use as u or dv.
    Just make the same substitution the second time.
    What happens is, you get back to the same integral,
    BUT with a different coefficient.
    Move that over to the left side and solve for the integral
    and do NOT forget the +C.
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  4. #4
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    Hey thanks guys! I don't know why I did not see that...even though I worked through the whole thing like twice!
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