# Vector Proof : Dot-products and Cross-Products

Show that (A x B).(C x D) = (A.C)(B.D) - (A.D)(B.C)

Show that [A x (B x C)].B = (A x B).(A x B)

https://brainmass.com/math/vector-calculus/vector-proof-dot-products-cross-products-142380

#### Solution Summary

A vector proof is provided. The solution is detailed and well presented. The response received a rating of "5/5" from the student who originally posted the question.

$2.19