Evaluate using suitable identities.497 × 505

1.	Evaluate using suitable identities.497 × 505
Answer» 497 × 505 = (500 – 3) (500 + 5) = 500² + (–3 + 5) × 500 + (–3) (5) [using (x + a) (x + b) = x² + (a + b) x + ab] = 250000 + 1000 – 15 = 250985

Answer»

497 × 505

= (500 – 3) (500 + 5)

= 500² + (–3 + 5) × 500 + (–3) (5) [using (x + a) (x + b) = x² + (a + b) x + ab]

= 250000 + 1000 – 15

= 250985

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