1. The problem statement, all variables and given/known data prove the idendity [tex] \sigma \times \sigma =i \sigma [/tex] where [tex] \sigma[/tex] is Pauli Spin matrices 2. Relevant equations 3. The attempt at a solution This is how I did..and I am getting 2[tex] i \sigma [/tex] instead of [tex] i\sigma [/tex]. http://i146.photobucket.com/albums/r273/soorajr/paulimatrix.jpg This question was asked twice for the university exam, and during both times, they asked us to prove [tex] \sigma \times \sigma =i \sigma [/tex]. Did i make any mistake? or the examiner was wrong? Thanks in advance.