Question

Tính:

\(\sqrt{19-6\sqrt{2}}\) 

Answer 1

`sqrt{19-6sqrt2}`

`=sqrt{18-2.3sqrt{2}+1]`

`=sqrt{(3sqrt2-1)^2}`

`=|3sqrt2-1|=3sqrt2-1`

Answer 2

\(\sqrt{19-6\sqrt{2}}=\sqrt{\left(3\sqrt{2}\right)^2-2\cdot3\sqrt{2}+1}=\sqrt{\left(3\sqrt{2}-1\right)^2}=3\sqrt{2}-1\)