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Math Help - Another DFQ

  1. #1
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    Another DFQ

    (dy/dt) - (3/t)y = 4(t^3)cos(5t) , y(pi) = 1
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  2. #2
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    Quote Originally Posted by DavidWagner View Post
    (dy/dt) - (3/t)y = 4(t^3)cos(5t) , y(pi) = 1
    This DE is first order linear and is solved using the integrating factor technique. Read your class notes, textbook or a website like Linear Equations for a refresher on the method.
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  3. #3
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    i got

    y= (4(t^3)sin(5t))/5 + t^3C

    then y(pi) implies C = -.184

    Is this correct?
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  4. #4
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    Quote Originally Posted by DavidWagner View Post
    i got

    y= (4(t^3)sin(5t))/5 + t^3C

    then y(pi) implies C = -.184

    Is this correct?
    Can't you check it yourself? I might get hit by a bus tomorrow, then where would you be ..... Empower yourself (and it's good practice for you too):

    Substitute x = \pi and check that it gives y = 1.

    Substitute the solution into the DE and check that it works.
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