If A=0xy0 and A3 + A = O then sum of possible values of xy is

A3+A=O⇒ AA2+I=O⇒  AA2+I=0⇒  |A|=0 or A2+I=0If |A|=0, then xy = 0A2+I=0xy00xy0+1001=xy00xy+1001=xy+100xy+1 A2+I=0⇒ (xy+1)2=0⇒ xy=−1So, sum of possible values of xy is -1.