Question

if x square + 1/x square = 38, find the value of x - 1/x.

Answer 1

x^2 + 1/x^2 = 38 
using identity 2 - we get - (x-1/x)^2 = x^2 - 2X x  X  1/x + 1/x ^2
                                                        =  38 -2 
                                                        =  36 
                                            x-1/x    =   root 36 = 6 

Answer 2

so answer of this question is positive negative 6