Linear Algebra by Gilbert strang, 4th edition, 5.1.13
If B has eigenvalues 1, 2, 3, C has eigenvalues 4, 5, 6, and D has eigenvalues 7, 8, 9, what are the eigenvalues of the 6 by 6 matrix A =[ B C , 0 D] ?
If B has eigenvalues 1, 2, 3, C has eigenvalues 4, 5, 6, and D has eigenvalues 7, 8,9, what are the eigenvalues of the 6 by 6 matrix A =[ B C , 0 D] ?