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Math Help - [SOLVED] First Order Differential Equation Help

  1. #1
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    [SOLVED] First Order Differential Equation Help

    Hey guys, I'm having a bit of trouble with this:

    Find the general solution to this differential equation, using the u=logy substitution



    The last line is what i got, but i get the feeling it is terribly wrong,

    So can you guys help me out?
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  2. #2
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    u=\ln y\implies u'=\frac{y'}{y}, besides y=e^u. Now put these in the ODE, you'll get a linear one easy to solve.
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  3. #3
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    Yeh I did that to get that answer in the original post,

    but i think i have calculated the integrating factor incorrectly, so can you help me out with that?
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  4. #4
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    Quote Originally Posted by jwade456 View Post
    Yeh I did that to get that answer in the original post,

    but i think i have calculated the integrating factor incorrectly, so can you help me out with that?
    Perhaps you can show your working?
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  5. #5
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    hey again,

    i just sorted it out (i was making a stupid mistake)

    sorry for wasting your time guys, and thanks for offering to help
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  6. #6
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    Quote Originally Posted by jwade456 View Post
    Hey guys, I'm having a bit of trouble with this:

    Find the general solution to this differential equation, using the u=logy substitution

    The last line is what i got, but i get the feeling it is terribly wrong,

    So can you guys help me out?
    Subsequently asked by a different member here:

    http://www.mathhelpforum.com/math-he...tml#post143673

    and replied to.
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