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    Just need some reassurance on these questions in terms of the cases..
    Attachment 508305508307
    Thankyou!
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    Hmm I am just looking at that paper and notice that there are some derivatives there (dy/dx) however I am unsure of your question, could you please elaborate? Do you need help or have you already done the paper?
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    (Original post by maths10101)
    Just need some reassurance on these questions in terms of the cases..
    Attachment 508305508307
    Thankyou!
    Sorry, I don't understand what you want? Have you solved these?
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    post your workings and someone will check
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    (Original post by Zacken)
    Sorry, I don't understand what you want? Have you solved these?

    (Original post by TeeEm)
    post your workings and someone will check
    Attachment 508313508315508300

    Very sorry about the rotation of the screenshots, not sure why it's doing that!
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    your integration of

    1/(10y ) is incorrect...

    you cannot raise the power & divide by the power...

    instead rewrite 10y as an exponential...
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    (Original post by maths10101)
    Attachment 508313508315508300

    Very sorry about the rotation of the screenshots, not sure why it's doing that!
    Okay, Q1. There's no reason to be splitting into cases of x=0 and the negation of that. Why did you do so?

    Furthermore, why did you put x \neq \pm 1 for your solution? \ln |x^2 + 1| is always positive and \geq 1. If x = \pm 1 we get \ln |x^2 + 1| = \ln 2 which is perfectly defined.
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    (Original post by maths10101)
    Thankyou!
    Bear has taken care of your Q2.

    Again, why are you splitting into cases for Q3? You needn't.
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    (Original post by Zacken)
    Okay, Q1. There's no reason to be splitting into cases of x=0 and the negation of that. Why did you do so?

    Furthermore, why did you put x \neq \pm 1 for your solution? \ln |x^2 + 1| is always positive and \geq 1. If x = \pm 1 we get \ln |x^2 + 1| = \ln 2 which is perfectly defined.
    I was told that you had to consider the different cases of the differential equation? Since the question reads: Please solve the differential equations and write a non-trivial solution.
    Surely, x=0 would also be a solution/the equilibrium solution? Or am i wrong? i've just learnt this recently in lectures so my memory isn't up to scratcch sorry
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    (Original post by Zacken)
    Bear has taken care of your Q2.

    Again, why are you splitting into cases for Q3? You needn't.
    Would there be different cases for any of the questions then?
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    (Original post by maths10101)
    Would there be different cases for any of the questions then?
    I'll let someone with uni-level rigour take over, but I don't see why you need different cases for the questions.

    (Original post by maths10101)
    I was told that you had to consider the different cases of the differential equation? Since the question reads: Please solve the differential equations and write a non-trivial solution.
    Surely, x=0 would also be a solution/the equilibrium solution? Or am i wrong? i've just learnt this recently in lectures so my memory isn't up to scratcch sorry
    I don't see how that wording requires different cases? :dontknow:
 
 
 
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