I already have another question on #15. Is there a way to know algebraically that it doesn't exist, or do I just have to graph it?

Question

anonymous · Answer

depends largely on #15

anonymous · Answer

anonymous · Answer

Really sorry about that

anonymous · Answer

And 16 too

anonymous · Answer

15 aint got no limit because cosine is periodic, goes from -1 to 1 infinitely often

anonymous · Answer

16 no limit for the same reason
in fact that expression is undefined infinitely often

anonymous · Answer

But its cosine (2x)

anonymous · Answer

And not just cos (x). I am really confused. Do you just have to know this stuff?

anonymous · Answer

@Hero

hero · Answer

You should listen to @satellite73. He knows what he's talking about.

anonymous · Answer

No, I don't doubt that, he just logged off

anonymous · Answer

And I didn't understand how he knows that

hero · Answer

Look at the graph: https://www.desmos.com/calculator/axjc7ugwky Does it look like it approaches anything as x gets larger?

anonymous · Answer

I'm not allowed to use the graph

anonymous · Answer

Thats the issue

hero · Answer

You'll need to familiarize yourself with the basic graphs of such functions.

anonymous · Answer

OH I get it now. So any function that oscillates does not have a limit at infinity or negative infinity?

hero · Answer

anonymous · Answer

I don't really understand that

hero · Answer

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