C4 Maths help with separating the variables

Hi guys

I was wondering if someone could explain something to me. I have no idea what side the coefficients should go on when separating the variables.

eg:
dy/dx = (3y^2)/(2sin^2 2x)

Answer is:
∫ 1/(y^2) = ∫ 3/(2sin^2 2x)

Why doesn't the 3 go with the y? I read that you should keep coefficients as the numerator, in which case, why doesn't the 2 go with the y to the left hand side?

Thanks in advance!

It doesn't make any difference.