matlab problem HW

[Chad S]

Can we plot the characteristic equation using Wolfram Alpha to find
another root, do we have to figure out how to do it in Matlab, or do
we have to solve it by hand? I plan on using wolfram alpha to find the
second root, finding the other two by hand, and then use use Matlab to
solve the system of linear equations. Is this acceptable?

[Professor Laugesen]

Sure, plotting the characteristic polynomial with Wolfram Alpha is a
good idea, when you are looking for that second root.
Wolfram Alpha can probably find all of the roots of the characteristic
equation - so give that a try too.