Question

Thu gọn biểu thức:

D= \(\left(\frac{\sqrt{7}-7}{1-\sqrt{7}}-\frac{\sqrt{7}+1}{7+\sqrt{7}}\right):\frac{\sqrt{7}+1}{\sqrt{7}}-7\sqrt{\frac{1}{\sqrt{7}}}\)

Answer 1

\(\left(\frac{\sqrt{7}-7}{1-\sqrt{7}}-\frac{\sqrt{7}+1}{7+\sqrt{7}}\right):\frac{\sqrt{7}+1}{\sqrt{7}}-7\sqrt{\frac{1}{\sqrt{7}}}=\left(\sqrt{7}-\sqrt{7}\right):\frac{\sqrt{7}+1}{\sqrt{7}}-7\sqrt{\frac{1}{\sqrt{7}}}=-7\sqrt{\frac{1}{\sqrt{7}}}\)