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