Question

Tính nhanh

97\(^2\)+33\(^2\)-30\(^2\)+66.97

Answer 1

\(97^2+33^2-30^2+66.97\\ =97^2+2.33.97+33^2-30^2\\ =\left(97+33\right)^2-30^2\\ =\left[\left(97+33\right)-30\right]\left[\left(97+33\right)+30\right]\\ =\left(97+33-30\right)\left(97+33+30\right)=100\times160=16000\)

Answer 2

`= 97^2 + 3 . 66 . 66. 97`

`= 97^2 + 66 . 100`

`= 9409 + 6600`

`= 16009`