Question

Evaluate the following using suitable identify a) (9.8)² b)(103)²

Answer 1

1)
$( {9.8)}^{2} = ( {10 - 0.2)}^{2} \\ = ( {10)}^{2} - 2(10)(0.2) + ( {0.2)}^{2} \\ = 100 - 4 + 0.04 \\ = 100.04 - 4 \\ = 93.04 \: \: \: ans$
2)
$( {103)}^{2} = ( {100 + 3)}^{2} \\ = ( {100)}^{2} + 2(100)(3) + ( {3)}^{2} \\ = 10000 + 600 + 9 \\ = 10609$