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Metamath Proof Explorer


Theorem spanss2

Description: A subset of Hilbert space is included in its span. (Contributed by NM, 2-Jun-2004) (New usage is discouraged.)

Ref Expression
Assertion spanss2 A A span A

Proof

Step Hyp Ref Expression
1 ssintub A x S | A x
2 spanval A span A = x S | A x
3 1 2 sseqtrrid A A span A