4x(3x2+3)1/2 dx	=	2 3 u1/2 du	(from two steps ago)
	=	2 3 u3/2 3/2 + C	(taking the antiderivative)
	=	4 9 u3/2+ C	(simplifying the answer)
	=	4 9 (3x2+3)3/2+ C	(substituting back for u)