$$\sqrt {8 - 2\sqrt {15} } $$ is equal to = ?
A. $${\text{3}} - \sqrt 5 $$
B. $$\sqrt 5 - \sqrt 3 $$
C. $${\text{5}} - \sqrt 3 $$
D. $$\sqrt 5 + \sqrt 3 $$
Answer: Option B
Solution (By Examveda Team)
$$\eqalign{ & \sqrt {8 - 2\sqrt {15} } \cr & = \sqrt {5 + 3 - 2 \times \sqrt 5 \times \sqrt 3 } \cr & = \sqrt {{{\left( {\sqrt 5 } \right)}^2} + {{\left( {\sqrt 3 } \right)}^2} - 2 \times \sqrt 5 \times \sqrt 3 } \cr & = \sqrt {{{\left( {\sqrt 5 - \sqrt 3 } \right)}^2}} \cr & = \left( {\sqrt 5 - \sqrt 3 } \right) \cr} $$This Question Belongs to Arithmetic Ability >> Surds And Indices
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