Answer 1

Here, we will use the identity

\[\left( x + a \right)\left( x - b \right) = x^2 + \left( a - b \right)x - ab\]

\[103 \times 96\]

\[ = \left( 100 + 3 \right)\left( 100 - 4 \right)\]

\[ = {100}^2 + \left( 3 - 4 \right)100 - 3 \times 4\]

\[ = 10000 - 100 - 12\]

\[ = 9888\]