Đáp án + Giải thích các bước giải:
$\text{a)}$ $\sqrt[]{0,52}$
$=$$\sqrt[]{\frac{13}{25}}$
$=$$\frac{\sqrt[]{13}}{5}$
$------------$
$\text{b)}$ $\sqrt[]{(\sqrt[]{3}-2)²}$
$=$ |$\sqrt[]{3}$ $-$ $2^{}$|
$=$ $2^{}$ $-$ $\sqrt[]{3}$
$------------$
$\text{c)}$ $\sqrt[]{(5-\sqrt[]{20})²}$
$=$ $\sqrt[]{(5-2\sqrt[]{5})²}$
$=$ ${5-2\sqrt[]{5}}$
$#Sherry2007#$