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    When tackling complementary functions with particualr integral,
    in what form are the general solutions if the trial solution is form of:
    • px^2+qx+r
    • px+r
    • psinx+qcosx
    • Ae^(qx)
    • Axe^(qx)
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    (Original post by keisiuho)
    When tackling complementary functions with particualr integral,
    in what form are the general solutions if the trial solution is form of:
    • px^2+qx+r
    • px+r
    • psinx+qcosx
    • Ae^(qx)
    • Axe^(qx)
    It depends on the complementory function...
    it could be Ae^m1x + Be^m2x + P.I. if there are two real roots etc.

    not sure if i understand what you mean....
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    Let me upload the question.

    Why the general solution has so many terms?
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    (Original post by keisiuho)
    Let me upload the question.

    Why the general solution has so many terms?
    comp function will be the normal one (ie real distinct roots) i think.

    the particular integral will be y=Ae^(3x)

    if the 10e^3x was 10e^2x then you would have to use y=Axe^2x
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    also

    when youre finding the complimentary function how do you know which solution to put with what letter.

    for example, in that example you got +- 2 a the solutions for m.

    so you can have Ae^2x + Be^-2x OR Ae^-2x + Be^2x

    i suspect these things dont matter though right?

    well, wrong.

    working to get a particular solution the values of A and B i got were switched around with the values of the roots.

    does this matter though!?
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    (Original post by kikzen)
    also

    when youre finding the complimentary function how do you know which solution to put with what letter.

    for example, in that example you got +- 2 a the solutions for m.

    so you can have Ae^2x + Be^-2x OR Ae^-2x + Be^2x

    i suspect these things dont matter though right?

    well, wrong.

    working to get a particular solution the values of A and B i got were switched around with the values of the roots.

    does this matter though!?
    It doesn't matter.
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    (Original post by kikzen)
    also

    when youre finding the complimentary function how do you know which solution to put with what letter.

    for example, in that example you got +- 2 a the solutions for m.

    so you can have Ae^2x + Be^-2x OR Ae^-2x + Be^2x
    isnt it only applied when there is no particular integral but only complementary function?
 
 
 
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