Giải thích các bước giải:
a) $\sqrt[]{4-2√3}$ = $\sqrt[]{3-2√3+1}$ = $\sqrt[]{(√3-1)^2}$ = |$\sqrt[]{3}$ -1| = $\sqrt[]{3}$ -1
b) $\sqrt[]{5+2√6}$ = $\sqrt[]{3+2√2.√3+2}$ = $\sqrt[]{(√3+√2)^2}$ =|√3+√2|=$\sqrt[]{3}$ + $\sqrt[]{2}$
c) $\sqrt[]{12+2√35}$ = $\sqrt[]{7+2√7.√5+5}$ = $\sqrt[]{(√7+√5)^2}$ = | √7 + √5 |= $\sqrt[]{7}$ + $\sqrt[]{5}$
d) $\sqrt[]{18-2√65}$ = $\sqrt[]{13-2√13.√5+5}$ = $\sqrt[]{(√13-√5)^2}$ = |√13 - √5| = $\sqrt[]{13}$ - $\sqrt[]{5}$
