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Theorems · Theorem · functional analysis

norm_add_lt_of_not_sameRay

∀ {E : Type u_2} [inst : NormedAddCommGroup E] [inst_1 : NormedSpace ℝ E] [StrictConvexSpace ℝ E] {x y : E},
  ¬SameRay ℝ x y → ‖x + y‖ < ‖x‖ + ‖y‖

In a strictly convex space, if x and y are not in the same ray, then ‖x + y‖ < ‖x‖ + ‖y‖.

Defined in
Mathlib.Analysis.Convex.StrictConvexSpace
Cited by
3 results in Mathlib
Foundations
Depth 165 from the axioms · uses propext, Classical.choice, Quot.sound
Assumes
NormedAddCommGroupNormedSpaceStrictConvexSpace

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