Need Some Help With A Trig Problem

[MGRGRM]

So I've been working on this trig problem for a bit and I'm stuck because I'm not quite sure how to think about this or where to start.

The question is: For what values of A∈[0,2π) is each of the following equations true:
1. sinA=sin(A+π)
2. cotA=cosA

I really haven't done much work yet because I'm not quite understanding how to go about this, so if someone could give guidance on how to start, that would be appreciated.

 

[tkhunny]

$$\sin(A+\pi) = \sin(A)\cos(\pi)+\cos(A)\sin(\pi)$$
Where does that lead?

$$\cot(A) = \dfrac{\cos(A)}{\sin(A)}$$
Where does that lead?