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Frisky90
May21-11, 07:23 AM
I have the following diff.eq. (d^2)y/d(x^2) + 2 dy/dx + y = 0 , but I don't have the answer, so could you please check.

The general solution that I got is y= e^(-x)[Ax+B]
If we have that x=0 when y=3 and dy/dx=1 , Then the particular solution is y= e^(-x)[4x+3]?

Does someone know a good online calculator for second order diff. eq ? I couldn't find any.

Mute
May21-11, 10:36 AM
You should be able to check yourself. You can see that your solution satisfies your initial condtions. To check if it satisfies your differential equation, take the first and second derivatives, and then plug those back into the left hand side of your equation. If it really is a solution, everything should cancel out to give you zero.

TylerH
May21-11, 12:29 PM
Wolfram Alpha is good for checking answers. Just type in y''+2y'+y=0 and it'll do the rest. What it won't do is show its work, so you'll still have to know how to do the problems.

Do you know how to do these(homogeneous diff eqs)?