Assume F, G, H are arbitrary 3D vectors, then
$(\vec{F}$ x $\nabla) . (\vec{G}$ x $\vec{H}) = ((\vec{F}$ x $\nabla)$ x $\vec{G}) . \vec{H} - ((\vec{F}$ x $\nabla)$ x $\vec{H}) . \vec{G}$
I have tried to prove this as you can see here \ref{1}, what step should i take next or did i do something wrong?
