| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mulsasslem3.1 | ⊢ ( 𝜑  →  𝐴  ∈   No  ) | 
						
							| 2 |  | mulsasslem3.2 | ⊢ ( 𝜑  →  𝐵  ∈   No  ) | 
						
							| 3 |  | mulsasslem3.3 | ⊢ ( 𝜑  →  𝐶  ∈   No  ) | 
						
							| 4 |  | mulsasslem3.4 | ⊢ 𝑃  ⊆  ( (  L  ‘ 𝐴 )  ∪  (  R  ‘ 𝐴 ) ) | 
						
							| 5 |  | mulsasslem3.5 | ⊢ 𝑄  ⊆  ( (  L  ‘ 𝐵 )  ∪  (  R  ‘ 𝐵 ) ) | 
						
							| 6 |  | mulsasslem3.6 | ⊢ 𝑅  ⊆  ( (  L  ‘ 𝐶 )  ∪  (  R  ‘ 𝐶 ) ) | 
						
							| 7 |  | mulsasslem3.7 | ⊢ ( 𝜑  →  ∀ 𝑥𝑂  ∈  ( (  L  ‘ 𝐴 )  ∪  (  R  ‘ 𝐴 ) ) ∀ 𝑦𝑂  ∈  ( (  L  ‘ 𝐵 )  ∪  (  R  ‘ 𝐵 ) ) ∀ 𝑧𝑂  ∈  ( (  L  ‘ 𝐶 )  ∪  (  R  ‘ 𝐶 ) ) ( ( 𝑥𝑂  ·s  𝑦𝑂 )  ·s  𝑧𝑂 )  =  ( 𝑥𝑂  ·s  ( 𝑦𝑂  ·s  𝑧𝑂 ) ) ) | 
						
							| 8 |  | mulsasslem3.8 | ⊢ ( 𝜑  →  ∀ 𝑥𝑂  ∈  ( (  L  ‘ 𝐴 )  ∪  (  R  ‘ 𝐴 ) ) ∀ 𝑦𝑂  ∈  ( (  L  ‘ 𝐵 )  ∪  (  R  ‘ 𝐵 ) ) ( ( 𝑥𝑂  ·s  𝑦𝑂 )  ·s  𝐶 )  =  ( 𝑥𝑂  ·s  ( 𝑦𝑂  ·s  𝐶 ) ) ) | 
						
							| 9 |  | mulsasslem3.9 | ⊢ ( 𝜑  →  ∀ 𝑥𝑂  ∈  ( (  L  ‘ 𝐴 )  ∪  (  R  ‘ 𝐴 ) ) ∀ 𝑧𝑂  ∈  ( (  L  ‘ 𝐶 )  ∪  (  R  ‘ 𝐶 ) ) ( ( 𝑥𝑂  ·s  𝐵 )  ·s  𝑧𝑂 )  =  ( 𝑥𝑂  ·s  ( 𝐵  ·s  𝑧𝑂 ) ) ) | 
						
							| 10 |  | mulsasslem3.10 | ⊢ ( 𝜑  →  ∀ 𝑦𝑂  ∈  ( (  L  ‘ 𝐵 )  ∪  (  R  ‘ 𝐵 ) ) ∀ 𝑧𝑂  ∈  ( (  L  ‘ 𝐶 )  ∪  (  R  ‘ 𝐶 ) ) ( ( 𝐴  ·s  𝑦𝑂 )  ·s  𝑧𝑂 )  =  ( 𝐴  ·s  ( 𝑦𝑂  ·s  𝑧𝑂 ) ) ) | 
						
							| 11 |  | mulsasslem3.11 | ⊢ ( 𝜑  →  ∀ 𝑥𝑂  ∈  ( (  L  ‘ 𝐴 )  ∪  (  R  ‘ 𝐴 ) ) ( ( 𝑥𝑂  ·s  𝐵 )  ·s  𝐶 )  =  ( 𝑥𝑂  ·s  ( 𝐵  ·s  𝐶 ) ) ) | 
						
							| 12 |  | mulsasslem3.12 | ⊢ ( 𝜑  →  ∀ 𝑦𝑂  ∈  ( (  L  ‘ 𝐵 )  ∪  (  R  ‘ 𝐵 ) ) ( ( 𝐴  ·s  𝑦𝑂 )  ·s  𝐶 )  =  ( 𝐴  ·s  ( 𝑦𝑂  ·s  𝐶 ) ) ) | 
						
							| 13 |  | mulsasslem3.13 | ⊢ ( 𝜑  →  ∀ 𝑧𝑂  ∈  ( (  L  ‘ 𝐶 )  ∪  (  R  ‘ 𝐶 ) ) ( ( 𝐴  ·s  𝐵 )  ·s  𝑧𝑂 )  =  ( 𝐴  ·s  ( 𝐵  ·s  𝑧𝑂 ) ) ) | 
						
							| 14 |  | oveq1 | ⊢ ( 𝑥𝑂  =  𝑥  →  ( 𝑥𝑂  ·s  𝐵 )  =  ( 𝑥  ·s  𝐵 ) ) | 
						
							| 15 | 14 | oveq1d | ⊢ ( 𝑥𝑂  =  𝑥  →  ( ( 𝑥𝑂  ·s  𝐵 )  ·s  𝐶 )  =  ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 ) ) | 
						
							| 16 |  | oveq1 | ⊢ ( 𝑥𝑂  =  𝑥  →  ( 𝑥𝑂  ·s  ( 𝐵  ·s  𝐶 ) )  =  ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) ) ) | 
						
							| 17 | 15 16 | eqeq12d | ⊢ ( 𝑥𝑂  =  𝑥  →  ( ( ( 𝑥𝑂  ·s  𝐵 )  ·s  𝐶 )  =  ( 𝑥𝑂  ·s  ( 𝐵  ·s  𝐶 ) )  ↔  ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  =  ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) ) ) ) | 
						
							| 18 | 11 | adantr | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ∀ 𝑥𝑂  ∈  ( (  L  ‘ 𝐴 )  ∪  (  R  ‘ 𝐴 ) ) ( ( 𝑥𝑂  ·s  𝐵 )  ·s  𝐶 )  =  ( 𝑥𝑂  ·s  ( 𝐵  ·s  𝐶 ) ) ) | 
						
							| 19 |  | simprll | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  𝑥  ∈  𝑃 ) | 
						
							| 20 | 4 19 | sselid | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  𝑥  ∈  ( (  L  ‘ 𝐴 )  ∪  (  R  ‘ 𝐴 ) ) ) | 
						
							| 21 | 17 18 20 | rspcdva | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  =  ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) ) ) | 
						
							| 22 |  | oveq2 | ⊢ ( 𝑦𝑂  =  𝑦  →  ( 𝐴  ·s  𝑦𝑂 )  =  ( 𝐴  ·s  𝑦 ) ) | 
						
							| 23 | 22 | oveq1d | ⊢ ( 𝑦𝑂  =  𝑦  →  ( ( 𝐴  ·s  𝑦𝑂 )  ·s  𝐶 )  =  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 ) ) | 
						
							| 24 |  | oveq1 | ⊢ ( 𝑦𝑂  =  𝑦  →  ( 𝑦𝑂  ·s  𝐶 )  =  ( 𝑦  ·s  𝐶 ) ) | 
						
							| 25 | 24 | oveq2d | ⊢ ( 𝑦𝑂  =  𝑦  →  ( 𝐴  ·s  ( 𝑦𝑂  ·s  𝐶 ) )  =  ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) ) ) | 
						
							| 26 | 23 25 | eqeq12d | ⊢ ( 𝑦𝑂  =  𝑦  →  ( ( ( 𝐴  ·s  𝑦𝑂 )  ·s  𝐶 )  =  ( 𝐴  ·s  ( 𝑦𝑂  ·s  𝐶 ) )  ↔  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  =  ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) ) ) ) | 
						
							| 27 | 12 | adantr | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ∀ 𝑦𝑂  ∈  ( (  L  ‘ 𝐵 )  ∪  (  R  ‘ 𝐵 ) ) ( ( 𝐴  ·s  𝑦𝑂 )  ·s  𝐶 )  =  ( 𝐴  ·s  ( 𝑦𝑂  ·s  𝐶 ) ) ) | 
						
							| 28 |  | simprlr | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  𝑦  ∈  𝑄 ) | 
						
							| 29 | 5 28 | sselid | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  𝑦  ∈  ( (  L  ‘ 𝐵 )  ∪  (  R  ‘ 𝐵 ) ) ) | 
						
							| 30 | 26 27 29 | rspcdva | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  =  ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) ) ) | 
						
							| 31 |  | oveq2 | ⊢ ( 𝑧𝑂  =  𝑧  →  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧𝑂 )  =  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 ) ) | 
						
							| 32 |  | oveq2 | ⊢ ( 𝑧𝑂  =  𝑧  →  ( 𝐵  ·s  𝑧𝑂 )  =  ( 𝐵  ·s  𝑧 ) ) | 
						
							| 33 | 32 | oveq2d | ⊢ ( 𝑧𝑂  =  𝑧  →  ( 𝐴  ·s  ( 𝐵  ·s  𝑧𝑂 ) )  =  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) ) | 
						
							| 34 | 31 33 | eqeq12d | ⊢ ( 𝑧𝑂  =  𝑧  →  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧𝑂 )  =  ( 𝐴  ·s  ( 𝐵  ·s  𝑧𝑂 ) )  ↔  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  =  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) ) ) | 
						
							| 35 | 13 | adantr | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ∀ 𝑧𝑂  ∈  ( (  L  ‘ 𝐶 )  ∪  (  R  ‘ 𝐶 ) ) ( ( 𝐴  ·s  𝐵 )  ·s  𝑧𝑂 )  =  ( 𝐴  ·s  ( 𝐵  ·s  𝑧𝑂 ) ) ) | 
						
							| 36 |  | simprr | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  𝑧  ∈  𝑅 ) | 
						
							| 37 | 6 36 | sselid | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  𝑧  ∈  ( (  L  ‘ 𝐶 )  ∪  (  R  ‘ 𝐶 ) ) ) | 
						
							| 38 | 34 35 37 | rspcdva | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  =  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) ) | 
						
							| 39 |  | leftssno | ⊢ (  L  ‘ 𝐴 )  ⊆   No | 
						
							| 40 |  | rightssno | ⊢ (  R  ‘ 𝐴 )  ⊆   No | 
						
							| 41 | 39 40 | unssi | ⊢ ( (  L  ‘ 𝐴 )  ∪  (  R  ‘ 𝐴 ) )  ⊆   No | 
						
							| 42 | 4 41 | sstri | ⊢ 𝑃  ⊆   No | 
						
							| 43 | 42 19 | sselid | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  𝑥  ∈   No  ) | 
						
							| 44 | 2 | adantr | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  𝐵  ∈   No  ) | 
						
							| 45 | 43 44 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝑥  ·s  𝐵 )  ∈   No  ) | 
						
							| 46 |  | leftssno | ⊢ (  L  ‘ 𝐶 )  ⊆   No | 
						
							| 47 |  | rightssno | ⊢ (  R  ‘ 𝐶 )  ⊆   No | 
						
							| 48 | 46 47 | unssi | ⊢ ( (  L  ‘ 𝐶 )  ∪  (  R  ‘ 𝐶 ) )  ⊆   No | 
						
							| 49 | 6 48 | sstri | ⊢ 𝑅  ⊆   No | 
						
							| 50 | 49 36 | sselid | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  𝑧  ∈   No  ) | 
						
							| 51 | 45 50 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  ∈   No  ) | 
						
							| 52 | 1 | adantr | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  𝐴  ∈   No  ) | 
						
							| 53 |  | leftssno | ⊢ (  L  ‘ 𝐵 )  ⊆   No | 
						
							| 54 |  | rightssno | ⊢ (  R  ‘ 𝐵 )  ⊆   No | 
						
							| 55 | 53 54 | unssi | ⊢ ( (  L  ‘ 𝐵 )  ∪  (  R  ‘ 𝐵 ) )  ⊆   No | 
						
							| 56 | 5 55 | sstri | ⊢ 𝑄  ⊆   No | 
						
							| 57 | 56 28 | sselid | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  𝑦  ∈   No  ) | 
						
							| 58 | 52 57 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝐴  ·s  𝑦 )  ∈   No  ) | 
						
							| 59 | 58 50 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 )  ∈   No  ) | 
						
							| 60 | 51 59 | addscomd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  =  ( ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 )  +s  ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 ) ) ) | 
						
							| 61 | 60 | oveq1d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  =  ( ( ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 )  +s  ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) | 
						
							| 62 | 43 57 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝑥  ·s  𝑦 )  ∈   No  ) | 
						
							| 63 | 62 50 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 )  ∈   No  ) | 
						
							| 64 | 59 51 63 | addsubsassd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 )  +s  ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  =  ( ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 )  +s  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) ) | 
						
							| 65 | 61 64 | eqtrd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  =  ( ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 )  +s  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) ) | 
						
							| 66 | 65 | oveq1d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  +s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  =  ( ( ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 )  +s  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) )  +s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) ) | 
						
							| 67 | 51 63 | subscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  ∈   No  ) | 
						
							| 68 | 3 | adantr | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  𝐶  ∈   No  ) | 
						
							| 69 | 62 68 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 )  ∈   No  ) | 
						
							| 70 | 59 67 69 | addsassd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 )  +s  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) )  +s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  =  ( ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 )  +s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  +s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) ) ) | 
						
							| 71 | 22 | oveq1d | ⊢ ( 𝑦𝑂  =  𝑦  →  ( ( 𝐴  ·s  𝑦𝑂 )  ·s  𝑧𝑂 )  =  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧𝑂 ) ) | 
						
							| 72 |  | oveq1 | ⊢ ( 𝑦𝑂  =  𝑦  →  ( 𝑦𝑂  ·s  𝑧𝑂 )  =  ( 𝑦  ·s  𝑧𝑂 ) ) | 
						
							| 73 | 72 | oveq2d | ⊢ ( 𝑦𝑂  =  𝑦  →  ( 𝐴  ·s  ( 𝑦𝑂  ·s  𝑧𝑂 ) )  =  ( 𝐴  ·s  ( 𝑦  ·s  𝑧𝑂 ) ) ) | 
						
							| 74 | 71 73 | eqeq12d | ⊢ ( 𝑦𝑂  =  𝑦  →  ( ( ( 𝐴  ·s  𝑦𝑂 )  ·s  𝑧𝑂 )  =  ( 𝐴  ·s  ( 𝑦𝑂  ·s  𝑧𝑂 ) )  ↔  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧𝑂 )  =  ( 𝐴  ·s  ( 𝑦  ·s  𝑧𝑂 ) ) ) ) | 
						
							| 75 |  | oveq2 | ⊢ ( 𝑧𝑂  =  𝑧  →  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧𝑂 )  =  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) ) | 
						
							| 76 |  | oveq2 | ⊢ ( 𝑧𝑂  =  𝑧  →  ( 𝑦  ·s  𝑧𝑂 )  =  ( 𝑦  ·s  𝑧 ) ) | 
						
							| 77 | 76 | oveq2d | ⊢ ( 𝑧𝑂  =  𝑧  →  ( 𝐴  ·s  ( 𝑦  ·s  𝑧𝑂 ) )  =  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) ) | 
						
							| 78 | 75 77 | eqeq12d | ⊢ ( 𝑧𝑂  =  𝑧  →  ( ( ( 𝐴  ·s  𝑦 )  ·s  𝑧𝑂 )  =  ( 𝐴  ·s  ( 𝑦  ·s  𝑧𝑂 ) )  ↔  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 )  =  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) | 
						
							| 79 | 10 | adantr | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ∀ 𝑦𝑂  ∈  ( (  L  ‘ 𝐵 )  ∪  (  R  ‘ 𝐵 ) ) ∀ 𝑧𝑂  ∈  ( (  L  ‘ 𝐶 )  ∪  (  R  ‘ 𝐶 ) ) ( ( 𝐴  ·s  𝑦𝑂 )  ·s  𝑧𝑂 )  =  ( 𝐴  ·s  ( 𝑦𝑂  ·s  𝑧𝑂 ) ) ) | 
						
							| 80 | 74 78 79 29 37 | rspc2dv | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 )  =  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) ) | 
						
							| 81 | 51 69 63 | addsubsd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  =  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  +s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) ) | 
						
							| 82 | 14 | oveq1d | ⊢ ( 𝑥𝑂  =  𝑥  →  ( ( 𝑥𝑂  ·s  𝐵 )  ·s  𝑧𝑂 )  =  ( ( 𝑥  ·s  𝐵 )  ·s  𝑧𝑂 ) ) | 
						
							| 83 |  | oveq1 | ⊢ ( 𝑥𝑂  =  𝑥  →  ( 𝑥𝑂  ·s  ( 𝐵  ·s  𝑧𝑂 ) )  =  ( 𝑥  ·s  ( 𝐵  ·s  𝑧𝑂 ) ) ) | 
						
							| 84 | 82 83 | eqeq12d | ⊢ ( 𝑥𝑂  =  𝑥  →  ( ( ( 𝑥𝑂  ·s  𝐵 )  ·s  𝑧𝑂 )  =  ( 𝑥𝑂  ·s  ( 𝐵  ·s  𝑧𝑂 ) )  ↔  ( ( 𝑥  ·s  𝐵 )  ·s  𝑧𝑂 )  =  ( 𝑥  ·s  ( 𝐵  ·s  𝑧𝑂 ) ) ) ) | 
						
							| 85 |  | oveq2 | ⊢ ( 𝑧𝑂  =  𝑧  →  ( ( 𝑥  ·s  𝐵 )  ·s  𝑧𝑂 )  =  ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 ) ) | 
						
							| 86 | 32 | oveq2d | ⊢ ( 𝑧𝑂  =  𝑧  →  ( 𝑥  ·s  ( 𝐵  ·s  𝑧𝑂 ) )  =  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) ) | 
						
							| 87 | 85 86 | eqeq12d | ⊢ ( 𝑧𝑂  =  𝑧  →  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧𝑂 )  =  ( 𝑥  ·s  ( 𝐵  ·s  𝑧𝑂 ) )  ↔  ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  =  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) ) ) | 
						
							| 88 | 9 | adantr | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ∀ 𝑥𝑂  ∈  ( (  L  ‘ 𝐴 )  ∪  (  R  ‘ 𝐴 ) ) ∀ 𝑧𝑂  ∈  ( (  L  ‘ 𝐶 )  ∪  (  R  ‘ 𝐶 ) ) ( ( 𝑥𝑂  ·s  𝐵 )  ·s  𝑧𝑂 )  =  ( 𝑥𝑂  ·s  ( 𝐵  ·s  𝑧𝑂 ) ) ) | 
						
							| 89 | 84 87 88 20 37 | rspc2dv | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  =  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) ) | 
						
							| 90 |  | oveq1 | ⊢ ( 𝑥𝑂  =  𝑥  →  ( 𝑥𝑂  ·s  𝑦𝑂 )  =  ( 𝑥  ·s  𝑦𝑂 ) ) | 
						
							| 91 | 90 | oveq1d | ⊢ ( 𝑥𝑂  =  𝑥  →  ( ( 𝑥𝑂  ·s  𝑦𝑂 )  ·s  𝐶 )  =  ( ( 𝑥  ·s  𝑦𝑂 )  ·s  𝐶 ) ) | 
						
							| 92 |  | oveq1 | ⊢ ( 𝑥𝑂  =  𝑥  →  ( 𝑥𝑂  ·s  ( 𝑦𝑂  ·s  𝐶 ) )  =  ( 𝑥  ·s  ( 𝑦𝑂  ·s  𝐶 ) ) ) | 
						
							| 93 | 91 92 | eqeq12d | ⊢ ( 𝑥𝑂  =  𝑥  →  ( ( ( 𝑥𝑂  ·s  𝑦𝑂 )  ·s  𝐶 )  =  ( 𝑥𝑂  ·s  ( 𝑦𝑂  ·s  𝐶 ) )  ↔  ( ( 𝑥  ·s  𝑦𝑂 )  ·s  𝐶 )  =  ( 𝑥  ·s  ( 𝑦𝑂  ·s  𝐶 ) ) ) ) | 
						
							| 94 |  | oveq2 | ⊢ ( 𝑦𝑂  =  𝑦  →  ( 𝑥  ·s  𝑦𝑂 )  =  ( 𝑥  ·s  𝑦 ) ) | 
						
							| 95 | 94 | oveq1d | ⊢ ( 𝑦𝑂  =  𝑦  →  ( ( 𝑥  ·s  𝑦𝑂 )  ·s  𝐶 )  =  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) | 
						
							| 96 | 24 | oveq2d | ⊢ ( 𝑦𝑂  =  𝑦  →  ( 𝑥  ·s  ( 𝑦𝑂  ·s  𝐶 ) )  =  ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) ) ) | 
						
							| 97 | 95 96 | eqeq12d | ⊢ ( 𝑦𝑂  =  𝑦  →  ( ( ( 𝑥  ·s  𝑦𝑂 )  ·s  𝐶 )  =  ( 𝑥  ·s  ( 𝑦𝑂  ·s  𝐶 ) )  ↔  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 )  =  ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) ) ) ) | 
						
							| 98 | 8 | adantr | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ∀ 𝑥𝑂  ∈  ( (  L  ‘ 𝐴 )  ∪  (  R  ‘ 𝐴 ) ) ∀ 𝑦𝑂  ∈  ( (  L  ‘ 𝐵 )  ∪  (  R  ‘ 𝐵 ) ) ( ( 𝑥𝑂  ·s  𝑦𝑂 )  ·s  𝐶 )  =  ( 𝑥𝑂  ·s  ( 𝑦𝑂  ·s  𝐶 ) ) ) | 
						
							| 99 | 93 97 98 20 29 | rspc2dv | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 )  =  ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) ) ) | 
						
							| 100 | 89 99 | oveq12d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  =  ( ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) )  +s  ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) ) ) ) | 
						
							| 101 | 44 50 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝐵  ·s  𝑧 )  ∈   No  ) | 
						
							| 102 | 43 101 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) )  ∈   No  ) | 
						
							| 103 | 57 68 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝑦  ·s  𝐶 )  ∈   No  ) | 
						
							| 104 | 43 103 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  ∈   No  ) | 
						
							| 105 | 102 104 | addscomd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) )  +s  ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) ) )  =  ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) ) ) | 
						
							| 106 | 100 105 | eqtrd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  =  ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) ) ) | 
						
							| 107 | 90 | oveq1d | ⊢ ( 𝑥𝑂  =  𝑥  →  ( ( 𝑥𝑂  ·s  𝑦𝑂 )  ·s  𝑧𝑂 )  =  ( ( 𝑥  ·s  𝑦𝑂 )  ·s  𝑧𝑂 ) ) | 
						
							| 108 |  | oveq1 | ⊢ ( 𝑥𝑂  =  𝑥  →  ( 𝑥𝑂  ·s  ( 𝑦𝑂  ·s  𝑧𝑂 ) )  =  ( 𝑥  ·s  ( 𝑦𝑂  ·s  𝑧𝑂 ) ) ) | 
						
							| 109 | 107 108 | eqeq12d | ⊢ ( 𝑥𝑂  =  𝑥  →  ( ( ( 𝑥𝑂  ·s  𝑦𝑂 )  ·s  𝑧𝑂 )  =  ( 𝑥𝑂  ·s  ( 𝑦𝑂  ·s  𝑧𝑂 ) )  ↔  ( ( 𝑥  ·s  𝑦𝑂 )  ·s  𝑧𝑂 )  =  ( 𝑥  ·s  ( 𝑦𝑂  ·s  𝑧𝑂 ) ) ) ) | 
						
							| 110 | 94 | oveq1d | ⊢ ( 𝑦𝑂  =  𝑦  →  ( ( 𝑥  ·s  𝑦𝑂 )  ·s  𝑧𝑂 )  =  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧𝑂 ) ) | 
						
							| 111 | 72 | oveq2d | ⊢ ( 𝑦𝑂  =  𝑦  →  ( 𝑥  ·s  ( 𝑦𝑂  ·s  𝑧𝑂 ) )  =  ( 𝑥  ·s  ( 𝑦  ·s  𝑧𝑂 ) ) ) | 
						
							| 112 | 110 111 | eqeq12d | ⊢ ( 𝑦𝑂  =  𝑦  →  ( ( ( 𝑥  ·s  𝑦𝑂 )  ·s  𝑧𝑂 )  =  ( 𝑥  ·s  ( 𝑦𝑂  ·s  𝑧𝑂 ) )  ↔  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧𝑂 )  =  ( 𝑥  ·s  ( 𝑦  ·s  𝑧𝑂 ) ) ) ) | 
						
							| 113 |  | oveq2 | ⊢ ( 𝑧𝑂  =  𝑧  →  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧𝑂 )  =  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) | 
						
							| 114 | 76 | oveq2d | ⊢ ( 𝑧𝑂  =  𝑧  →  ( 𝑥  ·s  ( 𝑦  ·s  𝑧𝑂 ) )  =  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) | 
						
							| 115 | 113 114 | eqeq12d | ⊢ ( 𝑧𝑂  =  𝑧  →  ( ( ( 𝑥  ·s  𝑦 )  ·s  𝑧𝑂 )  =  ( 𝑥  ·s  ( 𝑦  ·s  𝑧𝑂 ) )  ↔  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 )  =  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) | 
						
							| 116 | 7 | adantr | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ∀ 𝑥𝑂  ∈  ( (  L  ‘ 𝐴 )  ∪  (  R  ‘ 𝐴 ) ) ∀ 𝑦𝑂  ∈  ( (  L  ‘ 𝐵 )  ∪  (  R  ‘ 𝐵 ) ) ∀ 𝑧𝑂  ∈  ( (  L  ‘ 𝐶 )  ∪  (  R  ‘ 𝐶 ) ) ( ( 𝑥𝑂  ·s  𝑦𝑂 )  ·s  𝑧𝑂 )  =  ( 𝑥𝑂  ·s  ( 𝑦𝑂  ·s  𝑧𝑂 ) ) ) | 
						
							| 117 | 109 112 115 116 20 29 37 | rspc3dv | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 )  =  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) | 
						
							| 118 | 106 117 | oveq12d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  =  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) | 
						
							| 119 | 81 118 | eqtr3d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  +s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  =  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) | 
						
							| 120 | 80 119 | oveq12d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 )  +s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  +s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) )  =  ( ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) )  +s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) | 
						
							| 121 | 66 70 120 | 3eqtrd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  +s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  =  ( ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) )  +s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) | 
						
							| 122 | 38 121 | oveq12d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  +s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) )  =  ( ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) )  -s  ( ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) )  +s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) ) | 
						
							| 123 | 52 44 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝐴  ·s  𝐵 )  ∈   No  ) | 
						
							| 124 | 123 50 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  ∈   No  ) | 
						
							| 125 | 51 59 | addscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  ∈   No  ) | 
						
							| 126 | 125 63 | subscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  ∈   No  ) | 
						
							| 127 | 124 126 69 | subsubs4d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  =  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  +s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) ) ) | 
						
							| 128 | 52 101 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) )  ∈   No  ) | 
						
							| 129 | 57 50 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝑦  ·s  𝑧 )  ∈   No  ) | 
						
							| 130 | 52 129 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) )  ∈   No  ) | 
						
							| 131 | 104 102 | addscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  ∈   No  ) | 
						
							| 132 | 43 129 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) )  ∈   No  ) | 
						
							| 133 | 131 132 | subscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) )  ∈   No  ) | 
						
							| 134 | 128 130 133 | subsubs4d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) )  =  ( ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) )  -s  ( ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) )  +s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) ) | 
						
							| 135 | 122 127 134 | 3eqtr4d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  =  ( ( ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) | 
						
							| 136 | 30 135 | oveq12d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  +s  ( ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) )  =  ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) ) | 
						
							| 137 | 58 68 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  ∈   No  ) | 
						
							| 138 | 124 126 | subscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) )  ∈   No  ) | 
						
							| 139 | 137 138 69 | addsubsd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  +s  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  =  ( ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) ) ) | 
						
							| 140 | 137 138 69 | addsubsassd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  +s  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  =  ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  +s  ( ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) ) ) | 
						
							| 141 | 139 140 | eqtr3d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) )  =  ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  +s  ( ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) ) ) | 
						
							| 142 | 52 103 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  ∈   No  ) | 
						
							| 143 | 142 128 130 | addsubsassd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) )  =  ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) | 
						
							| 144 | 143 | oveq1d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) )  =  ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) | 
						
							| 145 | 128 130 | subscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) )  ∈   No  ) | 
						
							| 146 | 142 145 133 | addsubsassd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) )  =  ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) ) | 
						
							| 147 | 144 146 | eqtrd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) )  =  ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) ) | 
						
							| 148 | 136 141 147 | 3eqtr4d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) )  =  ( ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) | 
						
							| 149 | 21 148 | oveq12d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) ) )  =  ( ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) )  +s  ( ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) ) | 
						
							| 150 | 45 68 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  ∈   No  ) | 
						
							| 151 | 150 137 | addscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 ) )  ∈   No  ) | 
						
							| 152 | 151 69 | subscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  ∈   No  ) | 
						
							| 153 | 152 124 126 | addsubsassd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  +s  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 ) )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) )  =  ( ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) ) ) | 
						
							| 154 | 150 137 69 | addsubsassd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  =  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) ) ) | 
						
							| 155 | 154 | oveq1d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) )  =  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) )  +s  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) ) ) | 
						
							| 156 | 137 69 | subscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  ∈   No  ) | 
						
							| 157 | 150 156 138 | addsassd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) )  +s  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) )  =  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) ) ) ) | 
						
							| 158 | 153 155 157 | 3eqtrd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  +s  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 ) )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) )  =  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) ) ) ) | 
						
							| 159 | 44 68 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝐵  ·s  𝐶 )  ∈   No  ) | 
						
							| 160 | 43 159 | mulscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) )  ∈   No  ) | 
						
							| 161 | 142 128 | addscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) )  ∈   No  ) | 
						
							| 162 | 161 130 | subscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) )  ∈   No  ) | 
						
							| 163 | 160 162 133 | addsubsassd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) )  =  ( ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) )  +s  ( ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) ) | 
						
							| 164 | 149 158 163 | 3eqtr4d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  +s  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 ) )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) )  =  ( ( ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) | 
						
							| 165 | 45 58 | addscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  ∈   No  ) | 
						
							| 166 | 165 62 68 | subsdird | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝐶 )  =  ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  ·s  𝐶 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) ) | 
						
							| 167 | 45 58 68 | addsdird | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  ·s  𝐶 )  =  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 ) ) ) | 
						
							| 168 | 167 | oveq1d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  ·s  𝐶 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  =  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) ) | 
						
							| 169 | 166 168 | eqtrd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝐶 )  =  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) ) ) | 
						
							| 170 | 169 | oveq1d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 ) )  =  ( ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  +s  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 ) ) ) | 
						
							| 171 | 165 62 50 | subsdird | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝑧 )  =  ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  ·s  𝑧 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) | 
						
							| 172 | 45 58 50 | addsdird | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  ·s  𝑧 )  =  ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) ) ) | 
						
							| 173 | 172 | oveq1d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  ·s  𝑧 )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) )  =  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) | 
						
							| 174 | 171 173 | eqtrd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝑧 )  =  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) | 
						
							| 175 | 170 174 | oveq12d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 ) )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝑧 ) )  =  ( ( ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝐶 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝐶 ) )  +s  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 ) )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  ·s  𝑧 )  +s  ( ( 𝐴  ·s  𝑦 )  ·s  𝑧 ) )  -s  ( ( 𝑥  ·s  𝑦 )  ·s  𝑧 ) ) ) ) | 
						
							| 176 | 103 101 | addscld | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  ∈   No  ) | 
						
							| 177 | 52 176 129 | subsdid | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝐴  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) )  =  ( ( 𝐴  ·s  ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) | 
						
							| 178 | 52 103 101 | addsdid | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝐴  ·s  ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) ) )  =  ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) ) ) | 
						
							| 179 | 178 | oveq1d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝐴  ·s  ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) )  =  ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) | 
						
							| 180 | 177 179 | eqtrd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝐴  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) )  =  ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) | 
						
							| 181 | 180 | oveq2d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) ) )  =  ( ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) | 
						
							| 182 | 43 176 129 | subsdid | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝑥  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) )  =  ( ( 𝑥  ·s  ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) | 
						
							| 183 | 43 103 101 | addsdid | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝑥  ·s  ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) ) )  =  ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) ) ) | 
						
							| 184 | 183 | oveq1d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( 𝑥  ·s  ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) )  =  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) | 
						
							| 185 | 182 184 | eqtrd | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝑥  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) )  =  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) | 
						
							| 186 | 181 185 | oveq12d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) ) )  -s  ( 𝑥  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) ) )  =  ( ( ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) )  +s  ( ( ( 𝐴  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝐴  ·s  ( 𝑦  ·s  𝑧 ) ) ) )  -s  ( ( ( 𝑥  ·s  ( 𝑦  ·s  𝐶 ) )  +s  ( 𝑥  ·s  ( 𝐵  ·s  𝑧 ) ) )  -s  ( 𝑥  ·s  ( 𝑦  ·s  𝑧 ) ) ) ) ) | 
						
							| 187 | 164 175 186 | 3eqtr4d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( ( ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 ) )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝑧 ) )  =  ( ( ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) ) )  -s  ( 𝑥  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) ) ) ) | 
						
							| 188 | 187 | eqeq2d | ⊢ ( ( 𝜑  ∧  ( ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 )  ∧  𝑧  ∈  𝑅 ) )  →  ( 𝑎  =  ( ( ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 ) )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝑧 ) )  ↔  𝑎  =  ( ( ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) ) )  -s  ( 𝑥  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) ) ) ) ) | 
						
							| 189 | 188 | anassrs | ⊢ ( ( ( 𝜑  ∧  ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 ) )  ∧  𝑧  ∈  𝑅 )  →  ( 𝑎  =  ( ( ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 ) )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝑧 ) )  ↔  𝑎  =  ( ( ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) ) )  -s  ( 𝑥  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) ) ) ) ) | 
						
							| 190 | 189 | rexbidva | ⊢ ( ( 𝜑  ∧  ( 𝑥  ∈  𝑃  ∧  𝑦  ∈  𝑄 ) )  →  ( ∃ 𝑧  ∈  𝑅 𝑎  =  ( ( ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 ) )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝑧 ) )  ↔  ∃ 𝑧  ∈  𝑅 𝑎  =  ( ( ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) ) )  -s  ( 𝑥  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) ) ) ) ) | 
						
							| 191 | 190 | 2rexbidva | ⊢ ( 𝜑  →  ( ∃ 𝑥  ∈  𝑃 ∃ 𝑦  ∈  𝑄 ∃ 𝑧  ∈  𝑅 𝑎  =  ( ( ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝐶 )  +s  ( ( 𝐴  ·s  𝐵 )  ·s  𝑧 ) )  -s  ( ( ( ( 𝑥  ·s  𝐵 )  +s  ( 𝐴  ·s  𝑦 ) )  -s  ( 𝑥  ·s  𝑦 ) )  ·s  𝑧 ) )  ↔  ∃ 𝑥  ∈  𝑃 ∃ 𝑦  ∈  𝑄 ∃ 𝑧  ∈  𝑅 𝑎  =  ( ( ( 𝑥  ·s  ( 𝐵  ·s  𝐶 ) )  +s  ( 𝐴  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) ) )  -s  ( 𝑥  ·s  ( ( ( 𝑦  ·s  𝐶 )  +s  ( 𝐵  ·s  𝑧 ) )  -s  ( 𝑦  ·s  𝑧 ) ) ) ) ) ) |