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SSC CHSL 2023 PYQ — Question 60

SSC CHSL - 13 March 2023 - Shift 2 • Quantitative Aptitude • Q60

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If x2+1x2=7x^2+\frac{1}{x^2}=7, then what is the value of x3+1x3x^3+\frac{1}{x^3}?

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Correct answer: B

Explanation

The correct answer is option 2 i.e. 18.

x2 + 1/x2 = 7

⇒ x + 1/x = √(7 + 2) = √9 = 3

⇒ x3 + 1/x3 = 33 - 3(3) = 27 - 9 = 18

Hence, the required value is 18.