$\sqrt{810 x 40}$ nhanh nhanh

2 câu trả lời

`#tnvt`

`\sqrt{810.40}`

`=\sqrt{81.10.4.10}`

`=\sqrt{9^2 .10^2 .2^2}`

`=\sqrt{9^2}.\sqrt{10^2}.\sqrt{2^2}`

`=|9|.|10|.|2|`

`=9.10.2`

`=18.10`

`=180`

 

`\sqrt{810.40}`

`=\sqrt{81.10.4.10}`

`=\sqrt{9^2 . 10^2 . 2^2}`

`=|9|.|10|.|2|`

`=9.10.2`

`=180`

*Áp dụng công thức: `\sqrt{A^2}=|A|`