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    Please can someone explain to me step by step how to integrate: xlnx dx using integration by parts??

    I had a part that I got up to when I had to integrate (xlnx - x) and I got stuck here, but not sure if my steps before this were right,
    Thank you
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    you really want to end up differentiating the lnx part... it is much easier than integrating

    so that means you have to integrate the other bit, which is x....
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    (Original post by the bear)
    you really want to end up differentiating the lnx part... it is much easier than integrating

    so that means you have to integrate the other bit, which is x....
    Okay I will try and switch them round, do you know how I would integrate it in a scenario in which you had to?
    Thanks
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    (Original post by the bear)
    you really want to end up differentiating the lnx part... it is much easier than integrating

    so that means you have to integrate the other bit, which is x....
    My answer's got even worse
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    (Original post by jazz_xox_)
    Okay I will try and switch them round, do you know how I would integrate it in a scenario in which you had to?
    Thanks
    you would never need to during an integration by parts.

    but the answer is xlnx - x + c
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    (Original post by jazz_xox_)
    My answer's got even worse
    ∫ xlnx dx

    u = lnx

    du/dx = 1/x
    dv/dx= x

    v = x2/2

    ====> ∫ xlnx dx =(x2/2).lnx - ∫ x.1/x. dx

    etc
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    (Original post by the bear)
    ∫ xlnx dx

    u = lnx

    du/dx = 1/x
    dv/dx= x

    v = x2/2

    ====> ∫ xlnx dx =(x2/2).lnx - ∫ x.1/x. dx

    etc
    Got it! Thank you
 
 
 
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