Question

$rationalise \: the \: denomintor \:of \: \frac{1}{7 + 2 \sqrt{3} }$
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Answer 1

$= \frac{1}{7 + 2 \sqrt{3} } \\ = \frac{1}{7 + 2 \sqrt{3} } \times \frac{7 - 2 \sqrt{3} }{7 - 2 \sqrt{3} } \\ = \frac{7 - 2 \sqrt{3} }{( {7}^{2} ) -( {2 \sqrt{3}) }^{2} } \\ = \frac{7 - 2 \sqrt{ 3} }{49 - 12} \\= \frac{7 - 2 \sqrt{3} }{37}$

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