Member algo::qn::BroydenFletcherGoldfarbShanno< T >::calculateInverseHessian (const ublas::vector< double > &x1, const ublas::vector< double > &x2, const ublas::vector< double > &df1, const ublas::vector< double > &df2, const ublas::matrix< double > &H): check the first equation is correct or not.