×

x + 1/x = 3 We need to find: x³ + 1/x³

x + 1/x = 3 We need to find: x³ + 1/x³

Explanation

x³ + 1/x³ = (x + 1/x)³ − 3(x + 1/x)  

= 3³ − 3×3

= 27 − 9

= 18