Certificates for this sort of questions are discussed in my paper H. Schichl and A. Neumaier, [Transposition theorems and qualification-free optimality conditions][1], Siam J. Optimization 17 (2006), 1035-1055. They can be obtained numerically by [semidefinite programming][2]. [1]: http://arnold-neumaier.at/ms/trans.pdf [2]: https://en.wikipedia.org/wiki/Semidefinite_programming