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    Use the fact that e^x \sin 3x = Im (e^x e^{i3x}) to find \int e^x \sin 3x \, dx
    No idea how to do this. The book says nothing. Do I just integrate e^x e^{i3x} and take the imaginary part?
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    Yes. e^xe^{3ix} = e^{x(1+3i)} and it's just integrating e^(ax) but a is complex. Sigh, maths.
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    Thanks. Wasn't immediately obvious.
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    (Original post by Glutamic Acid)
    Yes. e^xe^{3ix} = e^{x(1+3i)} and it's just integrating e^(ax) but a is complex. Sigh, maths.
    Offtopic :
    Mate, could u clear ur inbox plz as i hav an imp msg to deliver!

    Thanks!!
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    (Original post by wizz_kid)
    Offtopic :
    Mate, could u clear ur inbox plz as i hav an imp msg to deliver!

    Thanks!!
    He's left TSR for good. Good luck trying to contact him if you don't know him well.
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    (Original post by SimonM)
    He's left TSR for good. Good luck trying to contact him if you don't know him well.
    OOO! Realy?! I wanted to ask him about a gap year maths course at the open uni. Would u happen to knoe abt it?
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    (Original post by wizz_kid)
    OOO! Realy?! I wanted to ask him about a gap year maths course at the open uni. Would u happen to knoe abt it?
    You'd do better asking Swayum or someone else who's actually done one
 
 
 
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