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Evaluate \(\frac{2}{6-5\sqrt{3}}\)

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Evaluate \(\frac{2}{6-5\sqrt{3}}\)

A.

\(-\left(\frac{12}{39}-\frac{10\sqrt{3}}{39}\right)\)

B.

\(\frac{12}{39}-\frac{10\sqrt{3}}{39}\)

C.

\(-\left(\frac{12}{39}+\frac{10\sqrt{3}}{39}\right)\)

D.

\(\frac{12}{39}+\frac{10\sqrt{3}}{39}\)

Correct answer is A

\(\frac{2}{6-5\sqrt{3}} = \frac{2}{6-5\sqrt{3}} \times \frac{6+5\sqrt{3}}{6+5\sqrt{3}}\\
=\frac{2(6+5\sqrt{3})}{(6-5\sqrt{3})(6+5\sqrt{3})}\\
=\frac{12+10-\sqrt{3}}{36-25(3)}\\
=\frac{12+10-\sqrt{3}}{36-75}\\
=\frac{12+10-\sqrt{3}}{-39}\\
=-\left(\frac{12}{39}-\frac{10\sqrt{3}}{39}\right)\)