12/12.16 Vector Analysis

Condition: for the field of vector \ (\ vec {a} = \ left (3 x^{2} y+2 x z^{3} \ right) \ vec {\ iMath}+\ left (x^{3} -\ right. \) \ (-2 y z) \ vec {\ jmath}+\ left (3 x^{2} z^{2} -y^{2} \ right) \ vec {k} \) Calculate \ (\ nabla \ cdot {a}) \ cdot | \ nabla \ Times \ Vec {a} |..