Question

tính nhanh

54^2+82^2-18^2-46^2

Answer 1

\(=\left(82^2-18^2\right)+\left(54^2-46^2\right)\\ =\left(82-18\right)\left(82+18\right)+\left(54-46\right)\left(54+46\right)\\ =64.100+8.100\\ =6400+800=7200\)

Answer 2

`54^{2}+82^{2}-18^{2}-46^{2}`

`=(54^{2}-46^{2})+(82^{2}-18^{2})`

`=(54-46)(54+46)+(82-18)(82+18)`

`=8.100+64.100`

`=100.(8+64)`

`=100.72=7200`