Question

if x-1/x:5 find x3-1/x3​

Answer 1

Step-by-step explanation:

$x - \frac{1}{x} = 5 \\ \\ sobs \\ \\ {x}^{2} + \frac{1}{ {x}^{2} } - 2 = 25 \\ \\ {x}^{2} + \frac{1}{ {x}^{2} } = 27 \\ \\ now \: wkt \\ \\ {x}^{3} - {y}^{3} = (x - y)( {x}^{2} + {y}^{2} + xy) \\ \\ now \\ \\ {x}^{3} - \frac{1}{ {x}^{3} } = (x - \frac{1}{x} )( {x}^{2} + \frac{1}{ {x}^{2} } + x \times \frac{1}{x} ) \\ \\ {x}^{3} - \frac{1}{ {x}^{3} } = 5(28) = 140$

hope it helps