Exams › SSC CGL (Prelims) › Maths

If x + \frac{1}{x} = 5, then x^2 + \frac{1}{x^2} = ?

1. 23
2. 27
3. 21
4. 29

Correct answer: 23

Solution

Given x + 1/x = 5. Squaring both sides gives x^2 + 1/x^2 + 2 = 25. Therefore, x^2 + 1/x^2 = 23. This is a direct application of an algebraic identity.

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