Find all eigenvalues of the matrix: A=(1224)A = \begin{pmatrix} 1 & 2 \\ 2 & 4 \end{pmatrix}A=(1224)
λ=0\lambda = 0λ=0 only
λ=5\lambda = 5λ=5 only
λ=0\lambda = 0λ=0 and λ=5\lambda = 5λ=5
λ=1\lambda = 1λ=1 and λ=4\lambda = 4λ=4