Đáp án+Giải thích các bước giải:
`(sqrt{3+2sqrt2}-sqrt{3-2sqrt2})(sqrt{3+2sqrt2}+sqrt{3-2sqrt2})`
`=(sqrt{2+2sqrt2+1}-sqrt{2-2sqrt2+1})(sqrt{2+2sqrt2+1}+sqrt{2-2sqrt2+1})`
`=(sqrt{(sqrt2+1)^2}-sqrt{(sqrt2-1)^2})(sqrt{(sqrt2+1)^2}+sqrt{(sqrt2-1)^2})`
`=(sqrt2+1-(sqrt2-1))(sqrt2+1+sqrt2-1)`
`=2.2sqrt2=4sqrt2`