>> It works like this and it's really easy to understand. The limit as X approaches either positive or negative infinity, for this fraction, is 0. Now here are the conditions within the fraction. Now X, this X is approaching infinity. It can have a, a rational exponent on it. Doesn't matter what the rational exponent is. Okay. It's a rational number to exponent on X. And C is any real number for the numerator. But if that, if this value approaches either positive or negative infinite, this fraction is approaching 0. You see because what's happening here, I mean think about this as just 1 for the moment. As X approaches infinity, or negative infinity. Let's say infinity for discussion purposes. As X gets big, big, big, big, big, as X gets really, really big, any fixed number over a really, really big number is getting smaller, and the fraction itself is getting smaller, and smaller, and smaller as X gets bigger and bigger and bigger. So this value, this fraction is approaching 0. Okay. And we can use that idea in a situation like this. The limit as X approaches infinity of this expression, and we can perform manipulations in, in this kind of limit at infinity as we did earlier. That is the limit of this difference is the difference of the limits. That is, it's the limit of this, minus the limit of that. We can think of it like that. The limit of a constant is the constant. The limit of this fraction, it fits the model you see of that idea, as X gets really, really big, then 7 over the X squared will go to nothingness. So this is 4 minus 0 or 4.