Marco G

I found this equations in this paper

Sorry the pdf is here by the way is not a homework i'm a pHD student

Hi everybody ! I have the follow equation : \qquad \mathbf{v}_l = \frac{1}{(1+A^2)}[\mathbf{B}-\mathbf{A}\times\mathbf{B} + (\mathbf{A} \cdot \mathbf{B} ) \mathbf{A} ] look the pdf I would verify (but I don't have Mathematica or other symbolic computing package license) that is correct and if yes how to get this (the step) thanks in advance Marco post2.pdf