How to Prove the Identity ∇×(u×v)=v∙∇u-u∙∇v+u∇∙v-v ∇∙u?

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SUMMARY

The identity ∇×(u×v)=v∙∇u-u∙∇v+u∇∙v-v ∇∙u, involving the vector triple product expansion, can be proven by expanding the del operator and applying it to the first vector while treating the second vector as constant, and then reversing the roles. It is essential to consider the general forms of vectors in Cartesian coordinates (i, j, k) and to verify both scalar and vector forms during the proof. This method, while tedious, is straightforward and effective for demonstrating the identity.

PREREQUISITES
  • Understanding of vector calculus and the del operator (∇).
  • Familiarity with vector triple product identities.
  • Knowledge of Cartesian coordinate systems (i, j, k).
  • Basic proficiency in scalar and vector multiplication concepts.
NEXT STEPS
  • Study vector calculus identities, specifically the vector triple product expansion.
  • Practice applying the del operator in various vector calculus problems.
  • Explore resources on scalar and vector multiplication to solidify understanding.
  • Consult advanced textbooks on vector calculus for deeper insights and examples.
USEFUL FOR

Students and professionals in mathematics, physics, and engineering who are looking to deepen their understanding of vector calculus and prove vector identities.

oxxiissiixxo
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Can any show me how you will go about proofing this identity

∇×(u×v)=v∙∇u-u∙∇v+u∇∙v-v ∇∙u where v and u are vectors

Many thanks.
 
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IT IS VECTOR TRIPLE PRODUCT EXPANSION

SIMPLY SOLVE IT BY EXPANDING DEL
AND APPLY IT TO FIRST VECTOR AND TAKING SECOND(VECTOR) CONSTANT AND THEN VICE VERSA.

U SHOULD ALSO ASSUME GENERAL DIFFIRENT FORMS OF VECTORS IN (I,J,K).

U SHOULD ALSO CHECK THE SCALAR AND VECTOR FORMS ,i.e,"X" & "." IS APPLIED B/W TWO VECTORS(WHICH GIVE AGAIN A VECTOR & SCALAR RESP.)

OR U SHOULD PREFER A GOOD BOOK.
 
Gobind, thank you for your post but please take off your Caps lock!

oxxiissiixxo, as Gobind says, the simplest way to prove that is probably to go ahead and doing the calculations. Tedious but not difficult.
 

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