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SSC CGL 2025 PYQ — Question 70

SSC CGL - 19 Sep 2025 - Shift 1 • Quantitative Aptitude • Q70

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If x+1x=−1x+\frac{1}{x}=-1, then compute x4+1x4+2x2+2x2x^4+\frac{1}{x^4}+2x^2+\frac{2}{x^2}

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Correct answer: A

Explanation

The correct answer is`option 1 i.e. -3.

x + 1/x = –1

x2 + 1/x2 = (x + 1/x)2 – 2 = 1 – 2 = –1

x4 + 1/x4 = (x2 + 1/x2)2 – 2 = 1 – 2 = –1

x4+1x4+2x2+2x2x^4+\frac{1}{x^4}+2x^2+\frac{2}{x^2}

= (x4 + 1/x4) + 2(x2 + 1/x2)

= –1 + 2(–1)

= –1 – 2

= –3