Đáp án+Giải thích các bước giải:
`a)A=\sqrt{(1-\sqrt3)^2}-\sqrt{(sqrt3+2)^2}`
`A=|1-sqrt3|-|sqrt3+2|`
`A=sqrt3-1-sqrt3-2`
`A=-3`
`b)B=sqrt{(2-sqrt3)^2}+sqrt{4-2sqrt3}`
`B=|2-sqrt3|+\sqrt{3-2sqrt3+1}`
`B=2-sqrt3+sqrt{(sqrt3-1)^2}`
`B=2-sqrt3+|sqrt3-1|`
`B=2-sqrt3+sqrt3-1=1`
`c)C=sqrt{15-6sqrt6}+sqrt{33-12sqrt6}`
`C=sqrt{9-2.3.sqrt6+6}+sqrt{24-2.3.2sqrt6+9}`
`C=sqrt{(3-sqrt3)^2}+sqrt{(2sqrt6-3)^2}`
`C=|3-sqrt3|+|2sqrt6-3|`
`C=3-sqrt3+2sqrt6-3`
`C=2sqrt6-sqrt3`
`d)D=sqrt{2-sqrt3}-sqrt{2+sqrt3}`
`D=sqrt{(4-2sqrt3)/2}-sqrt{(4+2sqrt3)/2}`
`D=sqrt{(3-2sqrt3+1)/2}-sqrt{(3+2sqrt3+1)/2}`
`D=sqrt{(sqrt3-1)^2/2}-sqrt{(sqrt3+1)^2/2}`
`D=(sqrt3-1)/sqrt2-(sqrt3+1)/sqrt2`
`D=(sqrt3-1-sqrt3-1)/sqrt2`
`D=(-2)/sqrt2=-sqrt2`
