Eigenvalue With a twist...

I get errors when manipulating a set a matrices A and B for a eig() function so i need to check it this way.

I'm trying to execute this particular format for an eigenvalue problem:

syms x; %where A and B is symetric but B has intermittent zeros on the diagonal. %

I'm trying to get the roots of this line of math but it doesnt seem to work. My code:

    keig=A\B;
    syms x
    I=(1/x).*eye(size(A));
    beep=det(keig-I)

Not sure how to get the roots from here.

I tried roots(keig,x) but to no avail. I get: too many input args

Error using roots

Too many input arguments.

Error in CriticalBuckleAnalysis (line 8)

bwep=roots(blep,x);

Ideas?

Answer 1

[Walter Roberson]

bwep = solve(beep, x)

This can be somewhat slow by 4 x 4 A, and by 5 x 5 it might just give you a bunch of roots() because of the inability to solve degree 5. However, you might be more interested in

factor(beep)

which gives four 1/x and a numerator and a denominator. The numerator term is linear in x (at least for the 4 x 4 test I did) leading to a single solution provided that the multiplier of x is not 0.