Find the characteristic polynomial and the eigenvalues of the matrix. 5 6 1 1 the characteristic polynomial is (type an expression using a 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. o 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.