Recent content by useruseruser

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    Graduate Using substiution of the form v=1/y^k to solve 1st order DE

    xy'+3y+4y^3=0 use substitution of the form v=1/y^k for some positive integer k. Choose a value of k that cancels the y^3 term.
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    Graduate How to tell if F(s) is laplace transform?

    Explain why the functions F(s)=\frac{s^2+4s+17}{s^5+16s^3+2^2+6} G(s)=\frac{2s}{(s^2+4)(\sqrt{1+s^2})} are Laplace transforms. (DO NOT TRY TO INVERT THESE LAPLACE TRANSFORMS) Is it something to do with some basic property of laplace transform?
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    Graduate What is the inverse Laplace transform of L^{-1}(\frac{1}{\sqrt{1+s^2}})?

    L^{-1}(\frac{1}{\sqrt{1+s^2}})=?
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    High School Solving y''=0: Understanding the Solution for y=c1+c2x

    It is said that y''=0 gives solution y=c1+c2x. How?
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    Graduate How Do You Solve a PDE with Boundary Conditions Using Separation of Variables?

    u_t=u_{xx}+2u_x 0<=x<=L, t>=0, u(x,0)=f(x), u_x(0,t)=u_x(L,t)=0 How to do this?