Metamath Proof Explorer


Theorem caov42d

Description: Rearrange arguments in a commutative, associative operation. (Contributed by NM, 26-Aug-1995) (Revised by Mario Carneiro, 30-Dec-2014)

Ref Expression
Hypotheses caovd.1 ( 𝜑𝐴𝑆 )
caovd.2 ( 𝜑𝐵𝑆 )
caovd.3 ( 𝜑𝐶𝑆 )
caovd.com ( ( 𝜑 ∧ ( 𝑥𝑆𝑦𝑆 ) ) → ( 𝑥 𝐹 𝑦 ) = ( 𝑦 𝐹 𝑥 ) )
caovd.ass ( ( 𝜑 ∧ ( 𝑥𝑆𝑦𝑆𝑧𝑆 ) ) → ( ( 𝑥 𝐹 𝑦 ) 𝐹 𝑧 ) = ( 𝑥 𝐹 ( 𝑦 𝐹 𝑧 ) ) )
caovd.4 ( 𝜑𝐷𝑆 )
caovd.cl ( ( 𝜑 ∧ ( 𝑥𝑆𝑦𝑆 ) ) → ( 𝑥 𝐹 𝑦 ) ∈ 𝑆 )
Assertion caov42d ( 𝜑 → ( ( 𝐴 𝐹 𝐵 ) 𝐹 ( 𝐶 𝐹 𝐷 ) ) = ( ( 𝐴 𝐹 𝐶 ) 𝐹 ( 𝐷 𝐹 𝐵 ) ) )

Proof

Step Hyp Ref Expression
1 caovd.1 ( 𝜑𝐴𝑆 )
2 caovd.2 ( 𝜑𝐵𝑆 )
3 caovd.3 ( 𝜑𝐶𝑆 )
4 caovd.com ( ( 𝜑 ∧ ( 𝑥𝑆𝑦𝑆 ) ) → ( 𝑥 𝐹 𝑦 ) = ( 𝑦 𝐹 𝑥 ) )
5 caovd.ass ( ( 𝜑 ∧ ( 𝑥𝑆𝑦𝑆𝑧𝑆 ) ) → ( ( 𝑥 𝐹 𝑦 ) 𝐹 𝑧 ) = ( 𝑥 𝐹 ( 𝑦 𝐹 𝑧 ) ) )
6 caovd.4 ( 𝜑𝐷𝑆 )
7 caovd.cl ( ( 𝜑 ∧ ( 𝑥𝑆𝑦𝑆 ) ) → ( 𝑥 𝐹 𝑦 ) ∈ 𝑆 )
8 1 2 3 4 5 6 7 caov4d ( 𝜑 → ( ( 𝐴 𝐹 𝐵 ) 𝐹 ( 𝐶 𝐹 𝐷 ) ) = ( ( 𝐴 𝐹 𝐶 ) 𝐹 ( 𝐵 𝐹 𝐷 ) ) )
9 4 2 6 caovcomd ( 𝜑 → ( 𝐵 𝐹 𝐷 ) = ( 𝐷 𝐹 𝐵 ) )
10 9 oveq2d ( 𝜑 → ( ( 𝐴 𝐹 𝐶 ) 𝐹 ( 𝐵 𝐹 𝐷 ) ) = ( ( 𝐴 𝐹 𝐶 ) 𝐹 ( 𝐷 𝐹 𝐵 ) ) )
11 8 10 eqtrd ( 𝜑 → ( ( 𝐴 𝐹 𝐵 ) 𝐹 ( 𝐶 𝐹 𝐷 ) ) = ( ( 𝐴 𝐹 𝐶 ) 𝐹 ( 𝐷 𝐹 𝐵 ) ) )