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Thread: hey I got some problem here if anyone can help me with my homework.. its urgent..

  1. #1
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    hey I got some problem here if anyone can help me with my homework.. its urgent..

    how to simplify and make y as the subject matter?
    -e^(-y)y-e^(-y)=sin^3x/3+c

    it will be great if anyone can help me
    thank you.

    From,Nurin.
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  2. #2
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    Re: hey I got some problem here if anyone can help me with my homework.. its urgent..

    Hey nurininsyirah97.

    You will need to introduce a transformation to find x as a function of y or y as a function of x.

    Try going both ways and see what you find [Hint - x as a function of y is probably easier] and consider the inverse function problem.
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  3. #3
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    Re: hey I got some problem here if anyone can help me with my homework.. its urgent..

    hmm its because i am doing a calculus which is first order differential eq. using separation of variables. and Ive reached to this part. and Im stuck here for hours. can u help me? T.T
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  4. #4
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    Re: hey I got some problem here if anyone can help me with my homework.. its urgent..

    An obvious first step is to factor out the e^{-y}:
    -e^{-y}(y+ 1)= \frac{sin^3(x)}{3}+ C.

    But you will not be able to solve for y as a function of x without using the "Lambert W function". Are you required to solve for y? It looks to me like you have already solved the differential equation.
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  5. #5
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    Re: hey I got some problem here if anyone can help me with my homework.. its urgent..

    lambert w function? what is that?
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