Metamath Proof Explorer


Theorem caov42

Description: Rearrange arguments in a commutative, associative operation. (Contributed by NM, 26-Aug-1995)

Ref Expression
Hypotheses caov.1 𝐴 ∈ V
caov.2 𝐵 ∈ V
caov.3 𝐶 ∈ V
caov.com ( 𝑥 𝐹 𝑦 ) = ( 𝑦 𝐹 𝑥 )
caov.ass ( ( 𝑥 𝐹 𝑦 ) 𝐹 𝑧 ) = ( 𝑥 𝐹 ( 𝑦 𝐹 𝑧 ) )
caov.4 𝐷 ∈ V
Assertion caov42 ( ( 𝐴 𝐹 𝐵 ) 𝐹 ( 𝐶 𝐹 𝐷 ) ) = ( ( 𝐴 𝐹 𝐶 ) 𝐹 ( 𝐷 𝐹 𝐵 ) )

Proof

Step Hyp Ref Expression
1 caov.1 𝐴 ∈ V
2 caov.2 𝐵 ∈ V
3 caov.3 𝐶 ∈ V
4 caov.com ( 𝑥 𝐹 𝑦 ) = ( 𝑦 𝐹 𝑥 )
5 caov.ass ( ( 𝑥 𝐹 𝑦 ) 𝐹 𝑧 ) = ( 𝑥 𝐹 ( 𝑦 𝐹 𝑧 ) )
6 caov.4 𝐷 ∈ V
7 1 2 3 4 5 6 caov4 ( ( 𝐴 𝐹 𝐵 ) 𝐹 ( 𝐶 𝐹 𝐷 ) ) = ( ( 𝐴 𝐹 𝐶 ) 𝐹 ( 𝐵 𝐹 𝐷 ) )
8 2 6 4 caovcom ( 𝐵 𝐹 𝐷 ) = ( 𝐷 𝐹 𝐵 )
9 8 oveq2i ( ( 𝐴 𝐹 𝐶 ) 𝐹 ( 𝐵 𝐹 𝐷 ) ) = ( ( 𝐴 𝐹 𝐶 ) 𝐹 ( 𝐷 𝐹 𝐵 ) )
10 7 9 eqtri ( ( 𝐴 𝐹 𝐵 ) 𝐹 ( 𝐶 𝐹 𝐷 ) ) = ( ( 𝐴 𝐹 𝐶 ) 𝐹 ( 𝐷 𝐹 𝐵 ) )