The values satisfying the equation are the eigenvalues of . Let us now consider this relation in more detail.

Statement

Given the matrix the expression is a polynomial of degree in .

Therefore, solving boils down to finding roots of a polynomial.

As much as this seems a feasible task for smaller degree polynomials (quadratic or cubic), finding roots of polynomials exactly can be a very hard task (see Abel–Ruffini theorem); at the same time, finding approximations of the roots numerically is relatively easy.