Recent content by whatababy

  1. W

    Graduate A tricky 2nd Oder ODE Problem,nonhomo delta=0 case

    Oh I made a silly mistake in differentiate the Yp... Yeah, you are right, I got the right answer now. Thanks
  2. W

    How Do You Solve a Tricky Second Order Nonhomogeneous Differential Equation?

    Homework Statement solve the initial value problem: y''+8.4y'+17.64y=e-4.2x y(0)=1, y'(0)=1 y(x)=? Homework Equations y=yc+yp The Attempt at a Solution The way I tried to achieve is to solve the corresponding homo equation first: y''+8.4y'+17.64y=0, which gives yc...
  3. W

    Graduate A tricky 2nd Oder ODE Problem,nonhomo delta=0 case

    solve the initial value problem: y''+8.4y'+17.64y=e-4.2x y(0)=1, y'(0)=1 y(x)=? The way I tried to achieve is to solve the corresponding homo equation first: y''+8.4y'+17.64y=0, which gives yc; yc=c1e-4.2x+c2e-4.2xx Then try to find yp, generally I would assume a yp=Ae-4.2x, but...
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    Graduate A second ODE problem that bothers me a lot HELP

    never mind, I got it.
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    Graduate A second ODE problem that bothers me a lot HELP

    A second ODE problem that bothers me a lot~~ HELP! The question is like: Find the function y1 of t which is the solution of: 9y''-36y'-45y=0 with initial conditions y1(0)=1, y'1(0)=0 y1= ? Find the function y2 of t which is the solution of: 9y''-36y'-45y=0 with initial conditions...