Question
Evaluate the following using identities: $117 \times 83$
✓
Answer
We have,
$117 \times 83$
$= (100 + 17)(100 - 17)$
$= (100)^2 - (17)^{2 }[(a + b)(a - b) = a^2 - b^2]$
$= 10000 - 289 [$Where $a = 100$ and $b = 17]$
$= 9711$
Therefore,$ 117 \times 83 = 9711$
$117 \times 83$
$= (100 + 17)(100 - 17)$
$= (100)^2 - (17)^{2 }[(a + b)(a - b) = a^2 - b^2]$
$= 10000 - 289 [$Where $a = 100$ and $b = 17]$
$= 9711$
Therefore,$ 117 \times 83 = 9711$
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