Question

x +1/x = 6 then find x³ + 1/x³​

Answer 1

$x + \frac{1}{x} = 6 \\ {x}^{3} + \frac{1}{ {x}^{3} } = ( {x + \frac{1}{x} })^{3} - 3(x + \frac{1}{x} ) \\ = {6}^{3} - 3 \times 6 \\ = 216 - 18 \\ = 198$