Metamath Proof Explorer


Theorem sspba

Description: The base set of a subspace is included in the parent base set. (Contributed by NM, 27-Jan-2008) (New usage is discouraged.)

Ref Expression
Hypotheses sspba.x X = BaseSet U
sspba.y Y = BaseSet W
sspba.h H = SubSp U
Assertion sspba U NrmCVec W H Y X

Proof

Step Hyp Ref Expression
1 sspba.x X = BaseSet U
2 sspba.y Y = BaseSet W
3 sspba.h H = SubSp U
4 eqid + v U = + v U
5 eqid + v W = + v W
6 eqid 𝑠OLD U = 𝑠OLD U
7 eqid 𝑠OLD W = 𝑠OLD W
8 eqid norm CV U = norm CV U
9 eqid norm CV W = norm CV W
10 4 5 6 7 8 9 3 isssp U NrmCVec W H W NrmCVec + v W + v U 𝑠OLD W 𝑠OLD U norm CV W norm CV U
11 10 simplbda U NrmCVec W H + v W + v U 𝑠OLD W 𝑠OLD U norm CV W norm CV U
12 11 simp1d U NrmCVec W H + v W + v U
13 rnss + v W + v U ran + v W ran + v U
14 12 13 syl U NrmCVec W H ran + v W ran + v U
15 2 5 bafval Y = ran + v W
16 1 4 bafval X = ran + v U
17 14 15 16 3sstr4g U NrmCVec W H Y X