Find the characteristic polynomial and the eigenvalues of the matrix. 6 3 3 6 The characteristic polynomial is □ (Type an expression using λ as the variable. Type an exact answer, using radicals as needed.) Select the correct choice below and, if necessary, fill in the answer box within your choice 0 A. The real eigenvalue(s) of the matrix is/are (Type an exact answer, using radicals as needed. Use a comma to separate answers as needed. Type each answer only once.) B. The matrix has no real eigenvalues.