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SSC CGL 2024 PYQ — Question 52

SSC CGL - 23 Sep 2024 - Shift 3 • Quantitative Aptitude • Q52

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Let 3t - 13t\frac{1}{3t} = 3, then which of the following expressions has the value equal to 12 ?

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Correct answer: C

Explanation

The correct answer is option 3 i.e. 9t2+19t2+19t^2 + \frac{1}{9t^2} + 1.

3t - 1/3t = 3

⇒ (3t - 1/3t)2 = 32 = 9

⇒ 9t2 - 2 + 1/9t2 = 9

⇒ 9t2 + 1/9t2 = 9 + 2 = 11

⇒ 9t2 + 1/9t2 + 1 = 11 + 1 = 12

Therefore, the required expression is 9t2 + 1/9t2​​​​​​​ + 1.