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    I seem to come up against the same problem when finding particular solutions to differential equations. I'm sure I'm missing out/doing something really stupid but I can't for the life of me seem to figure it out.

    E.g. When trying to solve:  dx/dt=x-5, given x=20 when t=0

    I get the answer  e^t+15 instead of the actual answer:  15e^t + 5

    Similarly for this question: -dy/dt=y+8, given y=10 when t=0; I get the answer e^-t +10 instead of the actual answer: 18e^-t -8

    Can anybody help or see where I'm going wrong?
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    (Original post by bloomingblossoms)
    I seem to come up against the same problem when finding particular solutions to differential equations. I'm sure I'm missing out/doing something really stupid but I can't for the life of me seem to figure it out.

    E.g. When trying to solve:  dx/dt=x-5, given x=20 when t=0

    I get the answer  e^t+15 instead of the actual answer:  15e^t + 5

    Similarly for this question: -dy/dt=y+8, given y=10 when t=0; I get the answer e^-t +10 instead of the actual answer: 18e^-t -8

    Can anybody help or see where I'm going wrong?
    I see where you've made a mistake, give me a minute to do it on a piece of paper and attach it!
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    (Original post by bloomingblossoms)
    I seem to come up against the same problem when finding particular solutions to differential equations. I'm sure I'm missing out/doing something really stupid but I can't for the life of me seem to figure it out.

    E.g. When trying to solve:  dx/dt=x-5, given x=20 when t=0

    I get the answer  e^t+15 instead of the actual answer:  15e^t + 5

    Similarly for this question: -dy/dt=y+8, given y=10 when t=0; I get the answer e^-t +10 instead of the actual answer: 18e^-t -8

    Can anybody help or see where I'm going wrong?
    Here you are!

    I'll do the second one too, if you like. It's good practise for me, ha!
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    (Original post by nukethemaly)
    Here you are!

    I'll do the second one too, if you like. It's good practise for me, ha!
    thank you!!!!
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    (Original post by bloomingblossoms)
    I seem to come up against the same problem when finding particular solutions to differential equations. I'm sure I'm missing out/doing something really stupid but I can't for the life of me seem to figure it out.

    E.g. When trying to solve:  dx/dt=x-5, given x=20 when t=0

    I get the answer  e^t+15 instead of the actual answer:  15e^t + 5

    Similarly for this question: -dy/dt=y+8, given y=10 when t=0; I get the answer e^-t +10 instead of the actual answer: 18e^-t -8

    Can anybody help or see where I'm going wrong?
    Here's the second one, hope it helps
    Been doing maths all day, and saw your thread so thought I'd take a crack at it

    Name:  2013-04-10 18.14.35.jpg
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