Last Diff Equation for today

I am asked to find the general solution, using the method of separating the variables of the following DE

dy/dx = (2xcos x)/y where y > 0

Using the method of seperating the variables I get:

int y.dy = int 2xcosx dx

which basically comes to (after a little working)

= 2 (cos x + xsinx)

but where do I go from here to get an integration constant?

2) If y = 2 when x = 0, find y in terms of x

Could someone help me on this one

3) Explain why your answer may not be used for x=pi. Comment in relation to the solution curve through (0,2).