Đáp án: + Giải thích các bước giải:
`B = ( 2/(\sqrt{3}-1) + 1/(\sqrt{3}-2) - 2/(1-\sqrt{2}) ).\sqrt{9-4\sqrt{2}}`
`= (9\sqrt{3}+5\sqrt{2}-3\sqrt{6}-15)/(5+3\sqrt{6}-5\sqrt{2}-3\sqrt{3}) . \sqrt{9-4\sqrt{2}}`
`= ((9\sqrt{3}+5\sqrt{2}-3\sqrt{6}-15)(2\sqrt{2}-1))/(5-5\sqrt{2}-3\sqrt{3}+3\sqrt{6})`
`= (21\sqrt{6}+35-21\sqrt{3}-35\sqrt{2})/(5-5\sqrt{2}-3\sqrt{3}+3\sqrt{6})`
`= (7(3\sqrt{6}+5-3\sqrt{3}-5\sqrt{2}))/(5-5\sqrt{2}-3\sqrt{3}+3\sqrt{6})`
`= 7`
