Question

What is the limit as x moves to negative infinity of cosx?

Answer 1

well if you think about cos x function as a graph, what happens when you move down the line of the graph?

Answer 2

towards -infinite

Answer 3

remember limits mean that the limit is a finite number. If you can't get to a finite number (as in a sinx or cosx graph) then the limit does not exist. It's considered a "wandering" graph.

Answer 4

However, you the function was cos x/2 that would be different, the key is to look at the graph, if it wanders the same then no limit, but if it gets smaller and smaller ("amplitude crusher" we used to call it) then that graph would have a limit.