Question

evaluate (99)^2 using formula

Answer 1

$99 {}^{2} = (100 - 1) {}^{2}$

$apply \: (a - b) {}^{2} = a {}^{2} + b {}^{2} - 2ab$

$100 {}^{2} + 1 {}^{2} - 2(100)(1)$

10000 + 1 - 200


9801


Thanks

Answer 2

=(100-1)^2
=(100)^2+ (1)^2-2(100)(1)
=10000+1-200
=9801