Question

If x + 1/x =5, find the value of xcube +1/xcube

Answer 1

Answer:

${x}^{3} + \frac{1}{ {x}^{3} } = (x + \frac{1}{x} ) {}^{3} - 3 \times x \times \frac{1}{x} (x + \frac{1}{x} ) =$

${5}^{3} - 3 \times 5 = 125 - 15 = 110 \: \: ans.$