prove that
Δ.(ΨΔφ x φΔΨ)=0
where Δ is delta.
anybody help plz
I do not disagree with reply #2 but I do wonder if by $\displaystyle \Delta$ you really mean $\displaystyle \nabla =i \frac{\partial }{{\partial x}} +j \frac{\partial }{{\partial y}} + k\frac{\partial }{{\partial z}}~?$
That is 'nabla' or the del operator. If not what does $\displaystyle \Delta$ mean?