If \(x + \frac{1}{x} = 3\), what is the value of \(x^3 + \frac{1}{x^3}\)?

A. 18

B. 24

C. 27

D. 21

Doubtly AI Asked 27 Oct 2026 AI-generated · not yet verified ssc cgl Save WhatsApp Report

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Answer: A. 18

Answer: (A) 18

Shortcut: \(x^3 + \frac{1}{x^3} = k^3 - 3k\) where k = 3: 27 − 9 = 18.

Doubtly AI · 27 Oct 2026 AI-generated · not yet verified Report

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