A is an n x n matrix. Mark each statement True or False. Justify each answer.
i. If A
x
=
λ
x
for some vectors, then λ
is an eigenvalue of A.
ii. A matrix A is not invertible if and only if 0 is an eigenvalue of A.
iii. A number c is an eigenvalue of A if and only if the equation (A - cI)x = 0 has a nontrivial solution.
iv. Finding an eigenvector of A may be difficult, but checking whether a given vector is in fact an eigenvector is easy.
v. To find the eigenvalues of A, reduce A to echelon form.