You will encounter limits at infinity in Math 20B when you learn about "improper" integrals in Section 7.8.

This video describes what a limit at infinity means, graphical examples of what situations you can get, the definition of horizontal asymptotes, and some specific limits we need to solve problems in this section.

This is a basic limit at infinity of a rational function, done both the textbook method's as well as the dominant term method.

This video deals with a problem where we have a root in our problem. We must include that root when dividing by the biggest power in the denominator.

This video does two problems, one going to positive infinity and the other to negative infinity, and the negative infinity one is tricky!

This video shows two more graphs that we must know--e^x and arctangent--to calculate other limits at infinity.

This video deals with limits at infinity involving a function composition and an arctangent.

This problem isn't a fraction! Ahh! How do we deal with that? We make it into one using the conjugate.

This limits at infinity problem involves a fraction with exponentials, and we go both to infinity and negative infinity. We will have to divide by different things on both of those!