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Operator questions

  1. Apr 22, 2009 #1
    I'm looking into vector calculus right now, and I have a few questions.

    * is the dot operator

    What is the difference between \nabla * F and F * \nabla ?

    What is \nabla ^2 F, where F is a vector field?
  2. jcsd
  3. Apr 22, 2009 #2


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    ∇⋅F is ∂(F_x)/∂x + ∂(F_y)/∂y + ∂(F_z)/∂z which is a scalar function. F⋅∇ is (F_x)(∂/∂x) + (F_y)(∂/∂y) + (F_z)(∂/∂z) which is an operator.

    ∇²F for a vector field F is just the vector field with components ∇²(F_x), ∇²(F_y) and ∇²(F_z).
  4. Apr 22, 2009 #3
    How did you get the symbols to work?
  5. Apr 22, 2009 #4
    f*del can be thought of as the directional derivative in the direction of f
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