Using identities, evaluate 992

992 = (100 − 1)2 = (100)2 − 2(100) (1) + (1)2 [(a − b)2 = a2 − 2ab + b2 ] = 10000 − 200 + 1 = 9801

Using Identities, Evaluate 99square2

Using identities, evaluate 99²

99² = (100 − 1)²

= (100)² − 2(100) (1) + (1)² [(a − b)² = a² − 2ab + b² ]

= 10000 − 200 + 1 = 9801

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