Solving Diff. Equations without MATLAB/Maple

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hey guys,

i have a Diff. equations assignment that requires MATLAB or maple to give me the roots to some DE's in order to solve them but I don't have the programs and can't spend the money on them right now, especially just for 1 assignment. so if you guys can just give me the roots it will help me a ton! the equations are:

y''' + 2y'' = 0

y''''-12y'''+86y''-300y'+625y=0

y'''+(5/6)y''+(1/6)y'=0

y'''+4y''=t^2

Thanks !
 
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You don't need MATLAB to get the characteristic roots to the DE.

Do you understand what is needed ?

Btw we do not give out answers until you have attempted the problem to a reasonable degree.
 
I haven't studied this section yet but my prof told me that we needed to use MATLAB or maple to get the roots, I am not sure if we need MATLAB for all of these DE's but i know for a fact that in order to solve the second DE I would need the roots before hand.
 
The roots are simple to get by mere inspection. Show us what you have done so far.

In MATLAB all you have to do is enter the coefficients of your characteristic polynomial and then use the roots command.
 
If you are looking for a straight answer, without work from your part - just go and use Maple to solve it.

This forum is for persons who are interested in how you get to the answer and not the answer itself.
 
Ok some clarification is needed

I have been lead to believe that one needs to know the roots in order to solve the DE and in order to get these roots you need maple/matlab. I don't have either of these programs and was wondering if someone could give me the roots so I COULD solve it. (meaning you guys wouldn't be just giving me the answer, i'd still have to do work it all out)

I have not learned most of this material yet so some of the DE's i posted may not need maple/matlab in order to get the roots (in which I will solve completely on my own) but for the ones that do require it (the second one, for instance) if i could just get the roots i will do the rest as I would need them in order to do the rest of the problem, no?
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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