Simplification · Question 15 · Hard
If x + 1/x = 5, find the value of x^3 + 1/x^3.
- 110
- 125
- 115
- 120
Answer and explanation
Answer: A. 110
Explanation: x^3 + 1/x^3 = (x + 1/x)^3 − 3(x + 1/x) = 125 − 15 = 110.
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