Linear Algebra Done Right · Problem 6A.22

Inner Product Spaces — Sheldon Axler

Mathematics — Linear Algebra · inner-products-and-norms

Problem

Show that if u,v∈Vu, v \in V, then ∥u+v∥ ∥u−v∥≤∥u∥2+∥v∥2.\|u + v\|\, \|u - v\| \leq \|u\|^2 + \|v\|^2.

Related theory

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