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Math Help - Integration problem.

  1. #1
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    Integration problem.

    Lost as to how to do this.
    Its not apparent if "Integration by parts" will work, or any substitutions. ((Came across this while working on differential equation problems, and half remembering learning how to do it before. So was hoping it wasn't too difficult))
    integral(2^xsinx)
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  2. #2
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    Quote Originally Posted by Frggr View Post
    Lost as to how to do this.
    Its not apparent if "Integration by parts" will work, or any substitutions. ((Came across this while working on differential equation problems, and half remembering learning how to do it before. So was hoping it wasn't too difficult))
    integral(2^xsinx)
    Did you try doing it by parts twice?
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  3. #3
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    Quote Originally Posted by Frggr View Post
    Lost as to how to do this.
    Its not apparent if "Integration by parts" will work, or any substitutions. ((Came across this while working on differential equation problems, and half remembering learning how to do it before. So was hoping it wasn't too difficult))
    integral(2^xsinx)
    integration by parts ...

    let u = \sin{x} , dv = 2^x \, dx

    you'll need to perform parts twice.
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  4. #4
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    Heh thanks. Realized my mistake. -- couldn't figure out
    integral(2^x)dx = v
    that you could sub
    let u = 2^x => ln(u) = xln(2)
    dx/du = 1/uln(2)

    etc.

    Was trying to:
    ln(v) = ln(integral(2^x)dx) = integral(ln(2^x)dx)
    which is just downright wrong.
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