# For lim as x -> -∞, how come lxl becomes -x?

1. Apr 16, 2012

### LearninDaMath

For lim as x --> -∞, how come lxl becomes -x?

1. The problem statement, all variables and given/known data

When you take the limit of a rational function as x approaches (-∞), I am dividing the numerator and denominator by the x value with highest exponent. Supposing the highest x value is √(x^2), so I divide the numerator and denominator by lxl. Then how come, in cases of x--> -∞, I am supposed to replace lxl with -x?

Does this question make sense?

2. Apr 16, 2012

### LearninDaMath

Re: For lim as x --> -∞, how come lxl becomes -x?

Nevermind, it clicked literally 15 seconds after posting the question. No help needed on this particular question anymore :)