Question

X^2+1/x^2=27, what is x-1/x=?

Answer 1

Step-by-step explanation:

$(x - \frac{1}{x} ) {}^{2} = {x}^{2} + \frac{1}{ {x}^{2} } - 2 = 27 - 2 = 25 \: \\ \implies \: x - \frac{1}{x} = \pm \: 5$