Variation of parameters problem, very BIG, but i think i'm right so far Diff EQ

mr_coffee
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OKay everyone, this is a big f'ing problem (to me anyways) and its only worth 1 point! But I'm doing it anyways. So here was my attempt, everything seems to be working out like it should but look at what u1 came out too, what am i going to do with that mess? Also do u see any mistakes? Thanks!
http://img86.imageshack.us/img86/6803/lastscan0rh.jpg
http://img86.imageshack.us/img86/2782/lastscan22bs.jpg
 
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That IS a lot of work. Are you sure that's how you're expected to solve these problem? Our friend Lagrange cooked up a crispy formula just for these occasions. It says that if y_1(t) and y_2(t) are linearly independant solution to the homogeneous equation y'' + p(t)y' + q(t)y = 0, then a particular solution to the inhomogeneous equation y'' + p(t)y' + q(t)y=g(t) is

Y(t) = -y_1 \int \frac{y_2 g}{W(y_1,y_2)}dt + y_2\int\frac{y_1 g}{W(y1,y_2)}dt
 
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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