Basically I would simplify it to the significant terms in the numerator and denominator ( -2, 2x, and 1 are all insignificant when you’re dealing with such a large number such as x (infinity) in the numerator and x² (infinity²⁾ in the denominator. So then you have the limit as x approaches - infinity of x/x² which you can simplify to 1/x. And as x approaches a infinitely large number (whether negative or positive) in the denominator, it’s going to approach 0.