Inequalities
In a normed vector space V, for example ℂn, the triangular inequality is ‖v + w‖ ≤ ‖v‖ + ‖w‖ for all v,w ∈ V. Besides the triangular inequality the Cauchy-Schwarz, Hölder's, Bessel's, Parseval's, Gibb's and Jensen's inequalities play a central role in mathematical and theoretical physics…