Simplification · Question 27 · Hard
If x = 3 + 2√2, find the value of x² + 1/x².
- 36
- 32
- 34
- 17
Answer and explanation
Answer: C. 34
Explanation: 1/x = 1/(3 + 2√2) = 3 − 2√2, so x + 1/x = 6. Then x² + 1/x² = (x + 1/x)² − 2 = 36 − 2 = 34.
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