Eigenvectors of coupled 2 different mass system

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SUMMARY

The discussion focuses on solving the coupled mass-spring problem for two different masses, represented by the equations (d/dt)²x1 = -2*w1*x1 + w1*x2 and (d/dt)²x2 = w2*x1 - 2*w2*x2, where w1 = k/m1 and w2 = k/m2. The user successfully derived the eigenvalues L1 and L2 but encountered difficulties when substituting these values back into the matrix to find the corresponding eigenvectors. The user ultimately resolved the issue independently, indicating that the problem is complex and often overlooked in literature.

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Homework Statement


Solve the coupled mass spring problem for two different masses. Similar to the Shankar example:
(d/dt)2x1=-2*w1*x1 + w1*x2
(d/dt)2x2=w2*x1 -2*w2*x2

where
w1= k/m1
w2 = k/m2

Homework Equations


Eigenvalue problem: UX=uX
Diagonalization: A=UDUt
Exponential Matrices: eA

The Attempt at a Solution


Starting off is simple enough. Taking the eigenvalue problem and solving for the eigenvalues.
L1 = -(w1+w2)+sqrt[ (w1+w2)2 - 3w1w2]
and L2 is the same as L1 but a minus in front of the sqrt

My problem lies when plugging back in the eigenvalues to solve for the eigenvectors. It seems straightforward but it is not. When plugging eigenvalues back into the matrix, trying to solve for eigenvector solution for both equations within the matrix is a tricky task.
Does anyone here know any required tricks that are needed to solve for the eigenvectors?

Many books stray away from this problem and resort to the system where the two masses are the same.
Any help is really appreciated.
 
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Please disregard this posting. I have figured the solution.
 

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