I managed to get the first couple questions in the section right..but as most of you know they get harder the farther you go. Currently these are the two I am stuck on. If somebody could show me how to solve them I can hopefully get the hang of the rest of them.

Decide whether the limits in the following problems exist. If a limit exist, find its value. The set of numbers should be next to the limit x approaching infinity but it came out sloppy so I just put them below.

Problem 1

lim

x-->infinity

x^2 + 6x + 8

x^3 + 2x + 1

Problem 2

lim

x-->-infinity

( 9/x^4 + 1/x^2 - 3)

Their are parentheses surrounding the entire problem except the limit(In other words from the 9/x^4 to the -3) I didn't put them as a fraction with an underline like problem 1 because they are seperate and it came out too sloppy, but you get the idea, it's 9 over x^4 plus 1 over x^2 minus 3

Thanks in advance for the help!