Given that the square matrix satisfies a ^ 2-2a + 2E = 0, it is proved that a and a-3e are invertible, and the inverse matrices of a and a-3e are obtained

Given that the square matrix satisfies a ^ 2-2a + 2E = 0, it is proved that a and a-3e are invertible, and the inverse matrices of a and a-3e are obtained

Because a ^ 2-2a + 2E = 0,
So a (a-2e) = - 2E
So a is reversible and a ^ - 1 = - 1 / 2 (a - 2e)
Then a ^ 2-2a + 2E = 0
A(A-3E) + (A-3E) +5E = 0
So (a + e) (a-3e) = - 5E
So a-3e is reversible and (a-3e) ^ - 1 = - 1 / 5 (a + e)