Value of (√2)³:
Numerical & Reasoning Ability ·Previously asked in JKSSB Constable (Executive / Armed / IRP / SDRF) 2017
View the full solved paper: J&K Police Constable 2017
Question
Value of (√2)³:
- A. 8
- B. 2
- C. 2√2 (Correct answer)
- D. None of the above
Correct Answer
Option C — 2√2
Detailed Solution & Explanation
The correct answer is 2√2.
Key Points
- (√2)³ = √2 × √2 × √2.
- The first two give √2 × √2 = 2, leaving 2 × √2 = 2√2.
- Numerically that is about 2.83, so the answer is neither 8 nor 2.
Additional Information
- Using index laws: (√2)³ = (2^½)³ = 2^(3/2) = 2¹ × 2^½ = 2√2.
- The rule to carry: (√a)ⁿ = a^(n/2), and √a × √a = a.
- Values worth memorising: √2 ≈ 1.414, √3 ≈ 1.732, √5 ≈ 2.236.
Topics covered: Surds Mathematics