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2 years ago

Using Suitable Identity ,Find the value of (i) (729)2-(271)2 (ii)98x107

Mathematics

1 answer:

pogonyaev2 years ago

3 0

Answer:

(i) 458000 (ii) 10486

Step-by-step explanation:

(i) (729)²-(271)²

The identity is : $a^2-b^2=(a-b)(a+b)$

(729)²-(271)² = (729-271) × (729+271)

= 458 × 1000

= 458000

(ii) 98x107 = (100-2) (100+7)

Idenity : $(x-a)(x-b) = x^2+(a+b)x+ab$

$(100-2) (100+7)=100^2+(-2+7)100+(-2)(7)\\\\=10000+500-14\\\\=10486$

Hence, this is the required solution.

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