If then verify that A2 + A = (A + I), where I is the identity matrix.
Given
We need to prove A2 + A = A (A + I).
Let us evaluate the LHS and the RHS one at a time.
To find the LHS, we will first calculate A2.
We know A2 = A × A
Now, the LHS is A2 + A.
To find the RHS, we will first calculate A + I.
Now, the RHS is A(A + I).
Thus, A2 + A = A (A + I).