Question

rationalise
$\frac{2 - \sqrt{5} }{2 + \sqrt{5} }$
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Answer 1

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Q:-rationalise

$\frac{2 - \sqrt{5} }{2 + \sqrt{5} }$

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------>>>>Here is your answer<<<<--------

$➾ \frac{2 - \sqrt{5} }{2 + \sqrt{5} } \times \frac{2 - \sqrt{5} }{2 - \sqrt{5} }$

$➾ \frac{ {(2 - \sqrt{5}) }^{2} }{ ({2})^{2} - { (\sqrt{5} )}^{2} }$

$➾ \frac{( {2})^{2} + { (\sqrt{5}) }^{2} - 2(2)( \sqrt{5} )}{4 - 5}$

$➾ \frac{4 + 5 - 4 \sqrt{5} }{1}$

$➾9 - 4 \sqrt{5}$

HOPE IT HELPS YOU..

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