Corrects SORM documentation

docs/source/reliability/sorm.rst

@@ -4,7 +4,7 @@ SORM
 In SORM the performance function is approximated by a second-order Taylor series around the design point according to
 
 
-.. math:: G(\textbf{U}) = G(\textbf{U}^\star) +  \nabla G(\textbf{U}^\star)(\textbf{U}-\textbf{U}^\star)^\intercal + \frac{1}{2}(\textbf{U}-\textbf{U}^\star)\textbf{H}(\textbf{U}-\textbf{U}^\star)
+.. math:: G(\textbf{U}) = G(\textbf{U}^\star) +  \nabla G(\textbf{U}^\star)(\textbf{U}-\textbf{U}^\star)^\intercal + \frac{1}{2}(\textbf{U}-\textbf{U}^\star)\textbf{H}(\textbf{U}-\textbf{U}^\star)(\textbf{U}-\textbf{U}^\star)^T
 
 where :math:`\textbf{H}` is the Hessian matrix of the second derivatives of :math:`G(\textbf{U})` evaluated at
 :math:`\textbf{U}^*`. After the design point :math:`\textbf{U}^*` is identified and the probability of failure