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Homework Help: Integrating Factor Method Problem

  1. Feb 5, 2012 #1
    1. The problem statement, all variables and given/known data

    Find the general solution of the given differential equation cosxy'+(sinx)y=1

    3. The attempt at a solution

    I divided everything by cosx and got : y'+(tanx)y=secx

    then after doing e to the integral of tanx i got : ∫d/dx[secx*y]=∫secx

    after integrating and simplifying i got y= ln|secx+tanx|/secx + Ccosx

    the answer in the book is y= sinx + Ccosx

    the weakest part of my math is simplifying (or algebra) what did i do wrong or what do i need to do?
  2. jcsd
  3. Feb 6, 2012 #2


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    When you multiplied by the integrating factor, you forgot to do it to the righthand side of the equation.
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