Algebra & Equations · Question 12 · Hard
If x + 1/x = 5, what is the value of x² + 1/x²?
- 21
- 27
- 25
- 23
Answer and explanation
Answer: D. 23
Explanation: Square both sides: x² + 2 + 1/x² = 25, so x² + 1/x² = 23.
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