MEIGENVAL(squared_matrix) returns the eigenvalues of a squared matrix entered as a range or array.  Note: While MSOLVE() returns a typical vertical range, MEIGENVAL() returns a horizontal range. This is done intentionally, so the user may compute the eigenvectors underneath the eigenvalues.  If values are complex numbers they are printed as strings.

In the screenshot below, the squared matrix is contained in the cell range A1:C3.  Cells E1:G1 contain the eigenvalues.

MEIGENVAL Function Parameters