Question

Rút gọn  \(\frac{1}{\sqrt{\frac{3}{5}}+\sqrt{\frac{3}{7}}+1}+\frac{1}{\sqrt{\frac{5}{3}}+\sqrt{\frac{5}{7}}+1}+\frac{1}{\sqrt{\frac{7}{3}}+\sqrt{\frac{7}{5}}+1}\)

Answer 1

\(\frac{1}{\text{ }\sqrt{\frac{3}{5}}+\sqrt{\frac{3}{7}}+1}=\frac{1}{\frac{\sqrt{3.7}+\sqrt{3.5}+\sqrt{5.7}}{\sqrt{5.7}}}=\frac{\sqrt{35}}{\sqrt{21}+\sqrt{35}+\sqrt{15}}\)

Tương tự :

 \(\frac{1}{\sqrt{\frac{5}{3}}+\sqrt{\frac{5}{7}}+1}=\frac{\sqrt{21}}{\sqrt{35}+\sqrt{15}+\sqrt{21}}\)

 

\(\frac{1}{\sqrt{\frac{7}{3}}+\sqrt{\frac{7}{5}}+1}=\frac{\sqrt{15}}{\sqrt{21}+\sqrt{35}+\sqrt{15}}\)

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