Given A=(2112)A = \begin{pmatrix} 2 & 1 \\ 1 & 2 \end{pmatrix}A=(2112), find λ\lambdaλ such that (A−λI)x=0(A - \lambda I)x = 0(A−λI)x=0 has a non-trivial solution.
λ=1,3\lambda = 1, 3λ=1,3
λ=2,2\lambda = 2, 2λ=2,2
λ=0,3\lambda = 0, 3λ=0,3
λ=1,2\lambda = 1, 2λ=1,2