Recent content by sassie

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    Solving the Sturm-Liouville System: Finding Eigenvalues and Eigenfunctions

    sorry, that was my fault. i wrote down the wrong ode, but mark44 pointed out the mistake. look's like I'm back at square 1.
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    Solving the Sturm-Liouville System: Finding Eigenvalues and Eigenfunctions

    Oh, okay! I was pondering why your RHS was the way it was. But can you help me with getting the equation into a form where I can the general solution? I REALLY need a hint to get me on the right track. I am sure I can solve for the eigenvalues and eigenfunctions myself, it's just been getting...
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    Solving the Sturm-Liouville System: Finding Eigenvalues and Eigenfunctions

    Re: EDIT Yes, so I am trying to get the general solutions to the given equation but I do not know how to.
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    Solving the Sturm-Liouville System: Finding Eigenvalues and Eigenfunctions

    I haven't even got the general ODE and that's what I have been having problems with. I have absolutely no idea how to obtain it :'( I know it should be easy but for the life of me, I can't do it
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    Solving the Sturm-Liouville System: Finding Eigenvalues and Eigenfunctions

    But can anyone help me with this question? I've been working on it for 5 hours straight and still I can't a solution! This question is just so much harder than ones I have handled previously!
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    Solving the Sturm-Liouville System: Finding Eigenvalues and Eigenfunctions

    Okay, what I did was (sorry I did skip a few steps): LHS = -(1+x^2)y''-2xy'-(\lambda \frac{1}{1 + x^2}) y=0 I then multiplied through by (1+x^2) ((1+x^{2})^{2})y''+2x(1+x^{2}) + \lambda y =0 Now, I understand how you got the left hand side of the equation you gave, I am a little...
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    Solving the Sturm-Liouville System: Finding Eigenvalues and Eigenfunctions

    Homework Statement Evaluate and find the eigenvalues and eigenfunctions for: -\frac{d}{dx}[(1+x^{2})\frac{dy}{dx}]=\lambda\frac{1}{1+x^{2}}y} Homework Equations The Attempt at a Solution Okay, what I did was to expand the given equation to get: ((1+x^{2})^{2})y''+2x(1+x^{2})y' + \lambda y...
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    Boundary Value Problem + Green's Function

    Please ignore. I figured out what I did wrong.
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    Boundary Value Problem + Green's Function

    Consider the BVP y''+4y=f(x) (0\leqx\leq1) y(0)=0 y'(1)=0 Find the Green's function (two-sided) for this problem. Working: So firstly, I let y(x)=Asin2x+Bcos2x Then using the boundary conditions, Asin(2.0)+Bcos(2.0)=0 => B=0 y'(x)=2Acos(2x)-2Asin(2x) y'(0)=2A=0...
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    Polynomial differential operators

    Homework Statement p(D) is a polynomial D operator of degree n>m. Suppose a is a m fold root of p(t)=0, but not a (m+1) fold root. Verify that \frac{1}{p(D)}e^{at}=\frac{1}{p^{(m)}(a)}t^me^{at} where p^{(m)}(t) is the m^{th} derivative of p(t).Homework Equations For this question, we were...
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    How Do You Apply the Heaviside Function in Green's Function Solutions?

    Homework Statement Find the solution for L[y]=H(t-pi/2)sint=q(t) y(0)=0 by using the Green's function. Homework Equations The Attempt at a Solution My problem is that I'm stuck with how to get the Heaviside into the required general solution. Is it anything to do with the fact that the...
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    Ordinary Differential Equations

    So what would we get when we integrate \delta(t-\tau)? would it be 1?
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    Ordinary Differential Equations

    Homework Statement Give the general solution to the IVP L[y]=y'+(sint)y=\delta(t-\tau) y(0)=0 For all t>0 by placing a jump condition on y(t) and solving the differential equation for t<\tau and t>\tau Homework Equations The Attempt at a Solution I'm plenty sure I can get the...
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