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ngovietthang


Rút gọn
[TEX]2\sqrt{20} - \frac {3\sqrt{60}}{\sqrt{3}} + \frac {\sqrt{21}}{7} - \frac {1}{\sqrt{3}}[/TEX]
[TEX]2\sqrt{20} - \frac {3\sqrt{60}}{\sqrt{3}} + \frac {\sqrt{21}}{7} - \frac {1}{\sqrt{3}}[/TEX]