Answer
The divergence is positive for the points above the $x$-axis and the negative for the points below the $x$-axis.
Work Step by Step
Divergence Theorem: $\iiint_Ediv \overrightarrow{F}dV=\iint_S \overrightarrow{F}\cdot d\overrightarrow{S} $
where, $div F=\dfrac{\partial P}{\partial x}+\dfrac{\partial Q}{\partial y}+\dfrac{\partial R}{\partial z}=\dfrac{\partial (xy)}{\partial x}+\dfrac{\partial b}{\partial (x+y^2)}=y+2y=3y$
The divergence will be negative when the net flow of water towards the inside and when the net flow of water is outwards, then the divergence at that point gets positive.
Also, The divergence will be zero when there is net flow of water either inwards or outwards.
Therefore, we get the divergence is positive for the points above the $x$-axis and the negative for the points below the $x$-axis.
