Question

Use appropriate formula to compute $1008\times 992$

Answer 1

Using the identity $(a+b)(a-b)$= $a^2-b^2$
Writing $1008$ as $1000+8$ and $992$ as $1000-8$
$\Rightarrow$ $\left(1008\right)\times \left(992\right)$ = $(1000+8)(1000-8)$
$\Rightarrow$ $(1000+8)(1000-8)$ = ${1000}^2-8^2$ $=$ $1000000-64$ $=$ $999936$
Hence the answer is $999936$