Aptitude Question ID: 107140

The value of \sqrt{8-2\sqrt{15}} is :
[A]3-\sqrt{5}
[B]5-\sqrt{3}
[C]\sqrt{5}-\sqrt{3}
[D]\sqrt{5}+\sqrt{3}

\mathbf{\sqrt{5}-\sqrt{3}}
Expression = \sqrt{8-2\sqrt{15}}
= \sqrt{5+3-2\sqrt{5}\times \sqrt{3}}
= \sqrt{(5)^{2}+(3)^{2}-2\sqrt{5}\times \sqrt{3}}
= \sqrt{(\sqrt{5}-\sqrt{3})^{2}} = \sqrt{5}-\sqrt{3}
Hence option [C] is correct answer.

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