I have worked through the following question with a period of 4 and got 4/n^2*pi^2 sin (n*pi/2) - 2/n*pi cos (n*pi) Can someone tell me why the cos part of the answer is n*pi and not (-1)^n?
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Well, You can convince yourself of this by looking at the graph of the cosine function. Does that answer your question?
so why would this be (-1)^2 and not the another?
I don't understand your question. Can you please rephrase?
The step before I got the answer of (-1)^2 was cos(n*pi) for post 3. The step before post 1 was cos(n*pi) and stayed cos(n*pi) and I dont know why.
Where did the (-1)^2 come from? I thought we were talking about (-1)^n. Did you mean (-1)^n in all your posts?
yeah sorry I do
Ah. So the answer to your question is post # 5 is that I have no clue. Post # 2 still stands. It could be a preference of the author, though I find the exponential expression to be simpler than the trig expression.
so the answer can be both in post #2
They're entirely equivalent. It's a preference thing.
or right, we were never told that in class. Thats helped me, thanks for that.
You're very welcome. Have a good one!
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