Question

evaluate 102×98 value without actual multiplication

Answer 1

Evaluate :

$\bf \: 102 \times 98 \\ \\ \bf \: we \: can \: write \: it \: as \\ \\ (100 + 2)( 100 - 2)$

Using the Identity :

$(a + b)(a - b) = {a}^{2} - {b}^{2}$

$= {(100)}^{2} - {(2)}^{2} \\ \\ = 10000 - 4 \\ \\ \bf \: = 9996$

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Answer 2

(100+2)(100-2)
square root of 100- square root of 2
10000-4
9996