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    solve the differntial equation d2y/dy2=625y given that y=3 and dy/dx=2 at x=0.

    how do i solve this?

    does it involve the general solution y=Ae^25x +Ae^-25x
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    (Original post by plmqaz)
    solve the differntial equation d2y/dy2=625y given that y=3 and dy/dx=2 at x=0.

    how do i solve this?

    does it involve the general solution y=Ae^25x +Ae^-25x
    I think you might have typed the equation wrong. Did you actually mean to type

    \dfrac{d^2y}{dx^2} = 625y ?
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    (Original post by EEngWillow)
    I think you might have typed the equation wrong. Did you actually mean to type

    \dfrac{d^2y}{dy^2} = 625y ?
    i don't know how to add supersubripts.
    i've just realised how to solve it thanks.
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    I assume you meant y=Ae^{25x}+Be^{-25x} as your general solution? The constants aren't the same.

    To find the particular solution, substitute x=0 and y=3; then differentiate it and set x=0 and dy/dx=2. This gives you two simultaneous equation for A and B that you can solve to find them. Then plugging these back into your general solution will give you the particular solution.

    EDIT: Too late :p: Never mind.
 
 
 
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