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Homework Help: Differential equations help!

  1. Dec 14, 2009 #1
    1. The problem statement, all variables and given/known data
    this problem was on my finals and i stared at it for 30 mins straight and still didn't figure it out and now it just bothers me that i don't know how to do the first problem on my final exam.

    "find the general solution to the dfq"
    xy'+xy= 1-y

    2. Relevant equations

    3. The attempt at a solution
    i dont think its linear cause if you do the integrating factor the right side is interms of x and y
    i don't think its separable... or multiplying by 1/x and subbing v for y/x could help
    i don't think its exact? or is it im not sure
    bernouli's formula wont help here.
    i don't know its probably something really stupid and easy... thanks for the help!
  2. jcsd
  3. Dec 14, 2009 #2


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    Science Advisor
    Homework Helper

    The y doesn't have to be on the right side. Write it as x*y'+(x+1)*y=1. Now divide by x and find the integrating factor.
  4. Dec 14, 2009 #3
    OH MY GOD. there goes 20 points that i should of gotten. thank you for the helpe.
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