$@Mốc$
`1)` $\sqrt{4+2\sqrt{3}}$ `-` $\sqrt{13+4\sqrt{3}}$
`=` $\sqrt{3+2\sqrt{3}+1}$ `-` $\sqrt{12+2.2\sqrt{3}+1}$
`=` $\sqrt{(\sqrt{3})^{2}+2\sqrt{3}.1+1^{2}}$ `-` $\sqrt{(2\sqrt{3})^{2}+2.2\sqrt{3}+1^2}$
`=` $\sqrt{(\sqrt{3}+1)^{2}}$ `-` $(\sqrt{2\sqrt{3}) + 1)^{2}}$
`=` $|\sqrt[]{3} + 1|$ `-` $|2\sqrt[]{3} + 1|$
`=` `\sqrt{3} + 1` `-` `2\sqrt{3}-1`
`=` `-\sqrt{3}`
$#chucbanhoctotnhe;333$
