Question

Plz help

9 grade..


If x^2 + 1/x^2=38.
So, find the value of (x - 1/x)

Answer 1

(x - 1/x)^2
= x^2 + 1/x^2 - 2x 1/x
x^2 + 1/x^2 - 2 =0
=36 (since, x^2 + 1/x^2 = 38)
Therefore, x - 1/x = 6.

Answer 2

Steps:

Subtract 2 from both sides.

RHS becomes 36 and LHS becomes square of something.

Then take the square root on both sides. RHS becomes 6 and LHS becomes something. Now that something is what you are seeking for.