Given the equation:
$$\left(\frac{1}{x^{2}} - \frac{1}{x}\right) - 6 = 0$$
Multiply the equation sides by the denominators:
x^2
we get:
$$x^{2} \left(\left(\frac{1}{x^{2}} - \frac{1}{x}\right) - 6\right) = 0$$
$$- 6 x^{2} - x + 1 = 0$$
This equation is of the form
a*x^2 + b*x + c = 0
A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
$$x_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$x_{2} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = -6$$
$$b = -1$$
$$c = 1$$
, then
D = b^2 - 4 * a * c =
(-1)^2 - 4 * (-6) * (1) = 25
Because D > 0, then the equation has two roots.
x1 = (-b + sqrt(D)) / (2*a)
x2 = (-b - sqrt(D)) / (2*a)
or
$$x_{1} = - \frac{1}{2}$$
$$x_{2} = \frac{1}{3}$$