If AAA is a 2×22 \times 22×2 matrix such that A2=IA^2 = IA2=I and A≠I,A≠−IA \neq I, A \neq -IA=I,A=−I, what are the possible eigenvalues?
1,11, 11,1
−1,−1-1, -1−1,−1
1,−11, -11,−1
0,00, 00,0