Exams › JEE Main › Maths
Given that a + 1/a = 3, compute the value of a³ + 1/a³.
- 18
- 0
- 9
- 27
Correct answer: 18
Solution
Cube the given sum and subtract three times the sum, since (a + 1/a)³ = a³ + 1/a³ + 3(a + 1/a).
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