QUE SIGNIFIE?

Further, critical points can be classified using the definiteness of the Hessian matrix: If the Hessian is positive definite at a critical abscisse, then the repère is a local minimal; if the Hessian matrix is negative definite, then the centre is a local acmé; finally, if indefinite, then the repère is some kind of saddle abscisse.L’audit tec