Jonathan T. answered • 06/11/19

Fun and Patient Calculus, Linear Algebra, Differential Equations Tutor

Eigenvalues pop up all over the place. You can find eigenvalues from an ODE e.g. y''-lambday=0 will output something like lambda=sin(nx) so to answer you question, yes the can be something other that a real number, they can be complex as well. They are not specific to matrices.