A generalized eigenvalue of a pair of matrices
is a scalar
for which there is a nonzero vector
satisfying
The vector
is called a generalized eigenvector of the matrix pair. The problem of finding such
pairs
is called a generalized eigenvalue problem.
If
is a nonsingular matrix, the generalized eigenvalues
are the ordinary eigenvalues of
. More generally, when the polynomial
is not identically zero,
the finite generalized eigenvalues are its roots, which
satisfy
This formulation includes many problems with constraints or nonstandard inner products without explicitly forming the matrix
inverse of .
The term generalized eigenvector is also used for a different concept associated with a single matrix.