9. Find the eigenvalues and bases of the corresponding eigenspaces of the matrix A : l? 21] Hint: you will have to use complex numbers 10. Assume that the two square matrices A and B commute, i.e., AB 2 BA. Let 6' E R\" be an eigenvector of A. Prove that BE" is also an eigenvector of A with the same eigenvalue, as long as Br? 75 U