We have this x term. But in the denominator we have two terms under the radical here. And as x gets larger and larger and larger, either in the positive or the negative direction, this x squared term is going to really dominate this one. You can imagine when x is a million, you're going to have a million squared plus 1. The value of the denominator is going to be dictated by this x squared term. So this is going to be approximately equal to x over the square root of x squared. This term right over here, the 1, isn't going to matter so much when we get very, very, very large x's.