General Solution to System of Equations w/o Eigenvalues

hbomb
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I have a question that involves a system of equations that I can't figure out

Give the general solution of the set of equations below:

x'=2x
y'=-x+3y
z'=2x-4y+6z

Hint: While you can use eigenvalues and eigenvectors for this one, there is an easier way to do it.

That's where I'm stuck, I know how to do this using the eigenvalues and eigenvectors.

This is a lower triangular matrix, so the eigenvalues are 2, 3, 6. But what's the other way of doing this?
 
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If x'=2x, what does x equal?

Plug that into the x for y' = -x + 3y, and solve for y.

Do the same for z then.

I find it a bit disconcerting that you have posted so many problems about these types of things, you may want to ask your professor to go over exactly what you're doing, since it looks like you just memorized the matrix formula and left it at that
 
Yea, he's very vague on some of these topics. He gives examples of finding determinants of matrices and finding eigenvalues and eigenvectors, but he never showed how to solve a system of equations with a given point.
 
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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