CDS 2015 PYQ with Answer — What is [√(5+√10)] / [5√5 − 2√20 − √32 + √50] equal to?

2015 · Q4

What is [√(5+√10)] / [5√5 − 2√20 − √32 + √50] equal to?

Elementary MathematicsNumber System

A5
B5{2}
C5{5}
D{5}

Explanation

DISPUTED — the stored key cannot be verified. Simplifying the denominator: 5√5 − 2√20 − √32 + √50 = 5√5 − 4√5 −4√2 + 5√2 = √5 + √2. The expression equals √(5+√10)/(√5+√2) ≈ 0.78, which matches none of the options (5, 5√2, 5√5, √5); the question/options are corrupted in the source. Stored key A retained; key disputed.