Using suitable identities, evaluate the following. (9.9)^2 - Vidyadip

Question

Using suitable identities, evaluate the following.
$(9.9)^2$

✓

Answer

$(9.9)^2$
$= (10 - 0.1)^2$
$= 10^2+ (0.1)^2- 2 × 10 × 0.1$
$= 100 + 0.01 - 2$
$= 98.01$

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