Metamath Proof Explorer


Theorem nv0lid

Description: The zero vector is a left identity element. (Contributed by NM, 28-Nov-2007) (Revised by Mario Carneiro, 21-Dec-2013) (New usage is discouraged.)

Ref Expression
Hypotheses nv0id.1 𝑋 = ( BaseSet ‘ 𝑈 )
nv0id.2 𝐺 = ( +𝑣𝑈 )
nv0id.6 𝑍 = ( 0vec𝑈 )
Assertion nv0lid ( ( 𝑈 ∈ NrmCVec ∧ 𝐴𝑋 ) → ( 𝑍 𝐺 𝐴 ) = 𝐴 )

Proof

Step Hyp Ref Expression
1 nv0id.1 𝑋 = ( BaseSet ‘ 𝑈 )
2 nv0id.2 𝐺 = ( +𝑣𝑈 )
3 nv0id.6 𝑍 = ( 0vec𝑈 )
4 2 3 0vfval ( 𝑈 ∈ NrmCVec → 𝑍 = ( GId ‘ 𝐺 ) )
5 4 oveq1d ( 𝑈 ∈ NrmCVec → ( 𝑍 𝐺 𝐴 ) = ( ( GId ‘ 𝐺 ) 𝐺 𝐴 ) )
6 5 adantr ( ( 𝑈 ∈ NrmCVec ∧ 𝐴𝑋 ) → ( 𝑍 𝐺 𝐴 ) = ( ( GId ‘ 𝐺 ) 𝐺 𝐴 ) )
7 2 nvgrp ( 𝑈 ∈ NrmCVec → 𝐺 ∈ GrpOp )
8 1 2 bafval 𝑋 = ran 𝐺
9 eqid ( GId ‘ 𝐺 ) = ( GId ‘ 𝐺 )
10 8 9 grpolid ( ( 𝐺 ∈ GrpOp ∧ 𝐴𝑋 ) → ( ( GId ‘ 𝐺 ) 𝐺 𝐴 ) = 𝐴 )
11 7 10 sylan ( ( 𝑈 ∈ NrmCVec ∧ 𝐴𝑋 ) → ( ( GId ‘ 𝐺 ) 𝐺 𝐴 ) = 𝐴 )
12 6 11 eqtrd ( ( 𝑈 ∈ NrmCVec ∧ 𝐴𝑋 ) → ( 𝑍 𝐺 𝐴 ) = 𝐴 )