Exams › JEE Main › Maths
If x + 1/x = 3, find the value of x³ + 1/x³.
- 9
- 18
- 27
- 6
Correct answer: 18
Solution
Using the identity (x + 1/x)³ = x³ + 1/x³ + 3(x + 1/x): 27 = x³ + 1/x³ + 9, so x³ + 1/x³ = 18.
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