generalization of the parallelogram law


Theorem.

In an inner product spaceMathworldPlanetmath (http://planetmath.org/InnerProductSpace), let x,y,z be vectors. Then

x+y2+y+z2+z+x2=x2+y2+z2+x+y+z2.

Taking x+z=0 we have the usual parallelogram lawMathworldPlanetmath.

Title generalizationPlanetmathPlanetmath of the parallelogram law
Canonical name GeneralizationOfTheParallelogramLaw
Date of creation 2013-03-22 16:08:53
Last modified on 2013-03-22 16:08:53
Owner Mathprof (13753)
Last modified by Mathprof (13753)
Numerical id 10
Author Mathprof (13753)
Entry type Theorem
Classification msc 46C05
Related topic ParallelogramLaw2