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Question
Evaluate the following product without multiplying directly:
95 × 96
Solution
95 × 96 = (100 − 5) (100 − 4)
= (100)2 + (− 5 − 4) 100 + (− 5) (− 4)
By using the identity (x + a)(x + b) = x2 + (a + b)x + ab,
where, x = 100, a = −5 and b = −4
= 10000 − 900 + 20
= 9120
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