The square root of (7 + 3√5)(7 − 3√5)

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The square root of (7 + 3√5)(7 − 3√5) is :

1. 4
2. √5
3. 3√5
4. 2

Correct Option: D

(7 + 3√5)(7 − 3√5) = (7)² − (3√5)²
= 49 – 45 = 4
∴ Required square root
= √4 = 2