Need help proving vector identities

dooogle
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Homework Statement



i have to prove that

∇x(FxG)=(G⋅∇)F-(F⋅∇)G+F(∇⋅G)-G(∇⋅F)

where F and G are vector fields with F=F1,F2,F3 and G=G1,G2,G3 ∇=d/dx,d/dy/d/dz

Homework Equations



The Attempt at a Solution



i have tried applying scalar multiplication and the cross product to multiply out the terms
and have got the right hand side as twice the left hand side.

is (G⋅∇)F equal to F(∇⋅G)?

thank you for your time

dooogle
 
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Do you know about the completely antisymmetric or Levi-Civita symbol \epsilon_{ijk}? This is by far the easiest way I know to prove this sort of identity.

dooogle said:
is (G⋅∇)F equal to F(∇⋅G)?

What if G is a constant vector and F is not?
 
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