Question

Using suitable identities evaluate the following:

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Answer 1

Step-by-step explanation:

(i) (2/4x - 3/2y)²

By using identity (a-b)²= a²+b²-2ab

=> (2/4x)²+(3/2y)²+ 2×2/4x ×3/2y

=> 4/16 x² + 9/4 y² - 6/4xy

=> 1/4 x² + 9/4 y²- 3/2xy

(ii) 98 × 103

(100.5 - 2.5) (100.5 + 2.5)

By using identity (a-b)(a+b) = a²-b²

=> (100.5)² - (2.5)²

=> 10,100.25 - 6.25

=> 10,094