Module 15 :  Vector fields, Gradient, Divergence and Curl
Lecture 44 :  Gradient Divergence and Curl [Section 44.1]
 

Then

  Thus, is irrotational. Hence, we have shown that every vector-field which has a potential is irrotational.
  We state next some properties of the curl operator which show that it behaves like a differential operator.
44.1.13 Theorem:
  Let be continuously differentiable vector-fields and a continuously differentiable Scalar-fields. Then the following hold:
(i)
(ii)
(iii)
where
   
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