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    • Thread Starter

    Hi I am stuck on two questions. I am a bit stuck on where to start.

    1) Solve the differential equation
    (tcos(xt)+(2xt^2)-(x^-2))dx/dt +xcos(xt) = 1-(2tx^2)
    subject to initail condition x=pi when t=1

    2) Solve the differential equation x.dy/dx +y +xy = e^-x
    with initial consition y=0 when x = 1

    For 1) I thought to find out if it is exact. By using p and q, differentiating to see if exact. Then integrating to find out h? But i think that is wrong.

    For 2) I thought dividing it through by x and rearranging to get dx/dy + y(1/x + 1) = e^-x
    and then using 1/x + 1 as the integrating factor?
    Can someone help me
    Thank you

    2) Your idea is correct:
    dy/dx + y(1/x + 1) = (e^-x)/x you mean.

    1) Is the question typed correctly?
    • Thread Starter

    (Original post by vc94)
    2) Your idea is correct:
    dy/dx + y(1/x + 1) = (e^-x)/x you mean.

    1) Is the question typed correctly?
    thank you.
    I shall try number 2 then.
    And no it wasnt typed correctly.
    Thank you for spotting. I have fixed it now.
    Any help is good
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Updated: March 26, 2011
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