Metamath Proof Explorer


Theorem subgdisjb

Description: Vectors belonging to disjoint commuting subgroups are uniquely determined by their sum. Analogous to opth , this theorem shows a way of representing a pair of vectors. (Contributed by NM, 5-Jul-2014) (Revised by Mario Carneiro, 19-Apr-2016)

Ref Expression
Hypotheses subgdisj.p + = ( +g𝐺 )
subgdisj.o 0 = ( 0g𝐺 )
subgdisj.z 𝑍 = ( Cntz ‘ 𝐺 )
subgdisj.t ( 𝜑𝑇 ∈ ( SubGrp ‘ 𝐺 ) )
subgdisj.u ( 𝜑𝑈 ∈ ( SubGrp ‘ 𝐺 ) )
subgdisj.i ( 𝜑 → ( 𝑇𝑈 ) = { 0 } )
subgdisj.s ( 𝜑𝑇 ⊆ ( 𝑍𝑈 ) )
subgdisj.a ( 𝜑𝐴𝑇 )
subgdisj.c ( 𝜑𝐶𝑇 )
subgdisj.b ( 𝜑𝐵𝑈 )
subgdisj.d ( 𝜑𝐷𝑈 )
Assertion subgdisjb ( 𝜑 → ( ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) ↔ ( 𝐴 = 𝐶𝐵 = 𝐷 ) ) )

Proof

Step Hyp Ref Expression
1 subgdisj.p + = ( +g𝐺 )
2 subgdisj.o 0 = ( 0g𝐺 )
3 subgdisj.z 𝑍 = ( Cntz ‘ 𝐺 )
4 subgdisj.t ( 𝜑𝑇 ∈ ( SubGrp ‘ 𝐺 ) )
5 subgdisj.u ( 𝜑𝑈 ∈ ( SubGrp ‘ 𝐺 ) )
6 subgdisj.i ( 𝜑 → ( 𝑇𝑈 ) = { 0 } )
7 subgdisj.s ( 𝜑𝑇 ⊆ ( 𝑍𝑈 ) )
8 subgdisj.a ( 𝜑𝐴𝑇 )
9 subgdisj.c ( 𝜑𝐶𝑇 )
10 subgdisj.b ( 𝜑𝐵𝑈 )
11 subgdisj.d ( 𝜑𝐷𝑈 )
12 4 adantr ( ( 𝜑 ∧ ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) ) → 𝑇 ∈ ( SubGrp ‘ 𝐺 ) )
13 5 adantr ( ( 𝜑 ∧ ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) ) → 𝑈 ∈ ( SubGrp ‘ 𝐺 ) )
14 6 adantr ( ( 𝜑 ∧ ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) ) → ( 𝑇𝑈 ) = { 0 } )
15 7 adantr ( ( 𝜑 ∧ ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) ) → 𝑇 ⊆ ( 𝑍𝑈 ) )
16 8 adantr ( ( 𝜑 ∧ ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) ) → 𝐴𝑇 )
17 9 adantr ( ( 𝜑 ∧ ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) ) → 𝐶𝑇 )
18 10 adantr ( ( 𝜑 ∧ ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) ) → 𝐵𝑈 )
19 11 adantr ( ( 𝜑 ∧ ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) ) → 𝐷𝑈 )
20 simpr ( ( 𝜑 ∧ ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) ) → ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) )
21 1 2 3 12 13 14 15 16 17 18 19 20 subgdisj1 ( ( 𝜑 ∧ ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) ) → 𝐴 = 𝐶 )
22 1 2 3 12 13 14 15 16 17 18 19 20 subgdisj2 ( ( 𝜑 ∧ ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) ) → 𝐵 = 𝐷 )
23 21 22 jca ( ( 𝜑 ∧ ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) ) → ( 𝐴 = 𝐶𝐵 = 𝐷 ) )
24 23 ex ( 𝜑 → ( ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) → ( 𝐴 = 𝐶𝐵 = 𝐷 ) ) )
25 oveq12 ( ( 𝐴 = 𝐶𝐵 = 𝐷 ) → ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) )
26 24 25 impbid1 ( 𝜑 → ( ( 𝐴 + 𝐵 ) = ( 𝐶 + 𝐷 ) ↔ ( 𝐴 = 𝐶𝐵 = 𝐷 ) ) )