Having trouble with graph of trig. function
I'm doing a graph sketching of
And I'm having trouble with two things:
Then, I checked on WolframAlpha and gives me an alternate form :
which is equivalent to what i got. But I have no idea how to go from the first form to the latter.
When taking limits of f(x) as x-> infinity and -infinity, I understand:
as x->+-inifinty ; i get y=1 and y=-1 as the horizontal asymptotes.
as x->+-infinity; i get y=1 and y=0 as the horizontal asymptotes.
Then for lim of cos^4(x) as x->+-infinity I get the same thing, but when those two are added, the graph is between the lines y=.5 and y=1
Any help would be greatly appreciated.