Use Identities to Evaluate : (998)2 - Mathematics

Use identities to evaluate : (998)²

Sum

(998)²
(998)² = (1000 - 2)²
We know that
( a - b )² = a² + b² - 2ab
∴ (1000 - 2)² = 1000² + 2² - 2 x 1000 x 2
= 1000000 + 4 - 4000
= 9,96,004

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Chapter 4: Expansions (Including Substitution) - Exercise 4 (A) [Page 57]

Chapter 4 Expansions (Including Substitution)
Exercise 4 (A) | Q 2.4 | Page 57

Evaluate the following using suitable identity:

(998)³

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8a³ – b³ – 12a²b + 6ab²

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x³ + y³ = (x + y) (x² – xy + y²)

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