2 câu trả lời
`(\sqrt2-1)\sqrt(3+2\sqrt2)`
`=(\sqrt2-1)\sqrt(2+2\sqrt(2).1+1)`
`=(\sqrt2-1)\sqrt((\sqrt(2)+1)^2)`
`=(\sqrt2-1)|\sqrt(2)+1|`
`=(\sqrt2-1)(\sqrt(2)+1)`
`=\sqrt(2^2)-1^2`
`=2-1`
`=1`
`(\sqrt2-1)\sqrt(3+2\sqrt2)`
`=(\sqrt2-1)\sqrt(2+2\sqrt(2).1+1)`
`=(\sqrt2-1)\sqrt((\sqrt(2)+1)^2)`
`=(\sqrt2-1)|\sqrt(2)+1|`
`=(\sqrt2-1)(\sqrt(2)+1)`
`=\sqrt(2^2)-1^2`
`=2-1`
`=1`