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MATH
[1251]

Theorems from Subspaces

All theorems from Subspaces.

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Subspace test

Let SS be a subset of a vector space VV over FF, with the operations inherited from VV. Then SS is a subspace of VV if and only if:

  1. SS is non-empty;
  2. SS is closed under vector addition: u,v∈Su,v\in S implies u+v∈Su+v\in S;
  3. SS is closed under scalar multiplication: u∈Su\in S and λ∈F\lambda\in F imply λu∈S\lambda u\in S.

Non-emptiness and scalar closure supply the zero vector and additive inverses, so these three conditions are enough.

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