Hi guys, I've got this differential equation:

And I've worked out the general solution when it is set equal to zero to be:

I need help finding the equation to set y(x) to so that i can solve the rest of it. Any clues?

Thanks in advance

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- Oct 16th 2008, 01:07 AMjwade4562nd Order Linear O.D.E. Help
Hi guys, I've got this differential equation:

And I've worked out the general solution when it is set equal to zero to be:

I need help finding the equation to set y(x) to so that i can solve the rest of it. Any clues?

Thanks in advance - Oct 16th 2008, 02:15 AMPeritus
- Oct 16th 2008, 05:09 PMJhevon
- Oct 16th 2008, 05:13 PMmr fantastic
- Oct 16th 2008, 05:33 PMJhevon
- Oct 16th 2008, 06:03 PMmr fantastic
- Oct 16th 2008, 06:54 PMJhevon
- Oct 16th 2008, 09:32 PMmr fantastic
- Oct 18th 2008, 08:38 PMU-God
So when what form would you have to take to solve the equation?

Furthermore, do you have to solve the equation with two different forms depending on whether or not alpha equals one, or is there a form that will work regardless of alpha's value?

Cheers. - Oct 18th 2008, 08:45 PMmr fantastic
- Oct 18th 2008, 08:52 PMU-God
Thanks mr fantastic, you certainly live up to your name!!

If I may ask just one more question, where did you get the form: from?

Is there a way I can derive it myself? Or is it just a rule of thumb.

Thanks again! - Oct 18th 2008, 08:57 PMmr fantastic
The informal answer is that it's the simplest form that works .....

obviously is no good so try the next simplest: .

That doesn't work so try the next simplest: . That works so it's all you need. Consider it a rule of thumb.

There*is*a way of getting it formally but I don't have the time to type out the details right now. Chris likes D.E.'s ... he might get a kick out of doing it. - Oct 18th 2008, 08:59 PMU-God
You have helped soooo much. Thanks again.

- Oct 18th 2008, 09:05 PMChris L T521
- Oct 19th 2008, 10:23 PMU-God
Thanks again,

I handed my work in and it all looks good, however some of my friends said that they did it by using the form .

You said here that that form wouldn't work and to move on to the next form up, so out of interest when I got home I tried it with form: and lo and behold I got the same answer as with form: .

Does that mean I did something wrong?

Cheers,