Question

Tính nhanh

2016^2-16^2

17.91,5+170.0,85

Answer 1

\(2016^2-16^2=\left(2020-4\right)^2-\left(20-4\right)^2=(4080400-16160+16)-\left(400-160+16\right)=4064256-256=4064000\)

Answer 2

\(2016^2-16^2=\left(2016-16\right)\left(2016+16\right)=2000.2022=4064000\)

\(17.91,5+170.0,85=17.91,5+17.10.0,85=17\left(91,5+8,5\right)\)

\(=17.100=1700.\)