| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mulclpr | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P )  →  ( 𝐴  ·P  𝐵 )  ∈  P ) | 
						
							| 2 | 1 | 3adant3 | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( 𝐴  ·P  𝐵 )  ∈  P ) | 
						
							| 3 |  | mulclpr | ⊢ ( ( 𝐴  ∈  P  ∧  𝐶  ∈  P )  →  ( 𝐴  ·P  𝐶 )  ∈  P ) | 
						
							| 4 |  | df-plp | ⊢  +P   =  ( 𝑥  ∈  P ,  𝑦  ∈  P  ↦  { 𝑓  ∣  ∃ 𝑔  ∈  𝑥 ∃ ℎ  ∈  𝑦 𝑓  =  ( 𝑔  +Q  ℎ ) } ) | 
						
							| 5 |  | addclnq | ⊢ ( ( 𝑔  ∈  Q  ∧  ℎ  ∈  Q )  →  ( 𝑔  +Q  ℎ )  ∈  Q ) | 
						
							| 6 | 4 5 | genpelv | ⊢ ( ( ( 𝐴  ·P  𝐵 )  ∈  P  ∧  ( 𝐴  ·P  𝐶 )  ∈  P )  →  ( 𝑤  ∈  ( ( 𝐴  ·P  𝐵 )  +P  ( 𝐴  ·P  𝐶 ) )  ↔  ∃ 𝑣  ∈  ( 𝐴  ·P  𝐵 ) ∃ 𝑢  ∈  ( 𝐴  ·P  𝐶 ) 𝑤  =  ( 𝑣  +Q  𝑢 ) ) ) | 
						
							| 7 | 2 3 6 | 3imp3i2an | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( 𝑤  ∈  ( ( 𝐴  ·P  𝐵 )  +P  ( 𝐴  ·P  𝐶 ) )  ↔  ∃ 𝑣  ∈  ( 𝐴  ·P  𝐵 ) ∃ 𝑢  ∈  ( 𝐴  ·P  𝐶 ) 𝑤  =  ( 𝑣  +Q  𝑢 ) ) ) | 
						
							| 8 |  | df-mp | ⊢  ·P   =  ( 𝑤  ∈  P ,  𝑣  ∈  P  ↦  { 𝑥  ∣  ∃ 𝑔  ∈  𝑤 ∃ ℎ  ∈  𝑣 𝑥  =  ( 𝑔  ·Q  ℎ ) } ) | 
						
							| 9 |  | mulclnq | ⊢ ( ( 𝑔  ∈  Q  ∧  ℎ  ∈  Q )  →  ( 𝑔  ·Q  ℎ )  ∈  Q ) | 
						
							| 10 | 8 9 | genpelv | ⊢ ( ( 𝐴  ∈  P  ∧  𝐶  ∈  P )  →  ( 𝑢  ∈  ( 𝐴  ·P  𝐶 )  ↔  ∃ 𝑓  ∈  𝐴 ∃ 𝑧  ∈  𝐶 𝑢  =  ( 𝑓  ·Q  𝑧 ) ) ) | 
						
							| 11 | 10 | 3adant2 | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( 𝑢  ∈  ( 𝐴  ·P  𝐶 )  ↔  ∃ 𝑓  ∈  𝐴 ∃ 𝑧  ∈  𝐶 𝑢  =  ( 𝑓  ·Q  𝑧 ) ) ) | 
						
							| 12 | 11 | anbi2d | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( ( 𝑣  ∈  ( 𝐴  ·P  𝐵 )  ∧  𝑢  ∈  ( 𝐴  ·P  𝐶 ) )  ↔  ( 𝑣  ∈  ( 𝐴  ·P  𝐵 )  ∧  ∃ 𝑓  ∈  𝐴 ∃ 𝑧  ∈  𝐶 𝑢  =  ( 𝑓  ·Q  𝑧 ) ) ) ) | 
						
							| 13 |  | df-mp | ⊢  ·P   =  ( 𝑤  ∈  P ,  𝑣  ∈  P  ↦  { 𝑓  ∣  ∃ 𝑔  ∈  𝑤 ∃ ℎ  ∈  𝑣 𝑓  =  ( 𝑔  ·Q  ℎ ) } ) | 
						
							| 14 | 13 9 | genpelv | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P )  →  ( 𝑣  ∈  ( 𝐴  ·P  𝐵 )  ↔  ∃ 𝑥  ∈  𝐴 ∃ 𝑦  ∈  𝐵 𝑣  =  ( 𝑥  ·Q  𝑦 ) ) ) | 
						
							| 15 | 14 | 3adant3 | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( 𝑣  ∈  ( 𝐴  ·P  𝐵 )  ↔  ∃ 𝑥  ∈  𝐴 ∃ 𝑦  ∈  𝐵 𝑣  =  ( 𝑥  ·Q  𝑦 ) ) ) | 
						
							| 16 |  | distrlem4pr | ⊢ ( ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  ∧  ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  ∧  ( 𝑓  ∈  𝐴  ∧  𝑧  ∈  𝐶 ) ) )  →  ( ( 𝑥  ·Q  𝑦 )  +Q  ( 𝑓  ·Q  𝑧 ) )  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) | 
						
							| 17 |  | oveq12 | ⊢ ( ( 𝑣  =  ( 𝑥  ·Q  𝑦 )  ∧  𝑢  =  ( 𝑓  ·Q  𝑧 ) )  →  ( 𝑣  +Q  𝑢 )  =  ( ( 𝑥  ·Q  𝑦 )  +Q  ( 𝑓  ·Q  𝑧 ) ) ) | 
						
							| 18 | 17 | eqeq2d | ⊢ ( ( 𝑣  =  ( 𝑥  ·Q  𝑦 )  ∧  𝑢  =  ( 𝑓  ·Q  𝑧 ) )  →  ( 𝑤  =  ( 𝑣  +Q  𝑢 )  ↔  𝑤  =  ( ( 𝑥  ·Q  𝑦 )  +Q  ( 𝑓  ·Q  𝑧 ) ) ) ) | 
						
							| 19 |  | eleq1 | ⊢ ( 𝑤  =  ( ( 𝑥  ·Q  𝑦 )  +Q  ( 𝑓  ·Q  𝑧 ) )  →  ( 𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) )  ↔  ( ( 𝑥  ·Q  𝑦 )  +Q  ( 𝑓  ·Q  𝑧 ) )  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) | 
						
							| 20 | 18 19 | biimtrdi | ⊢ ( ( 𝑣  =  ( 𝑥  ·Q  𝑦 )  ∧  𝑢  =  ( 𝑓  ·Q  𝑧 ) )  →  ( 𝑤  =  ( 𝑣  +Q  𝑢 )  →  ( 𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) )  ↔  ( ( 𝑥  ·Q  𝑦 )  +Q  ( 𝑓  ·Q  𝑧 ) )  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) ) | 
						
							| 21 | 20 | imp | ⊢ ( ( ( 𝑣  =  ( 𝑥  ·Q  𝑦 )  ∧  𝑢  =  ( 𝑓  ·Q  𝑧 ) )  ∧  𝑤  =  ( 𝑣  +Q  𝑢 ) )  →  ( 𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) )  ↔  ( ( 𝑥  ·Q  𝑦 )  +Q  ( 𝑓  ·Q  𝑧 ) )  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) | 
						
							| 22 | 16 21 | syl5ibrcom | ⊢ ( ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  ∧  ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  ∧  ( 𝑓  ∈  𝐴  ∧  𝑧  ∈  𝐶 ) ) )  →  ( ( ( 𝑣  =  ( 𝑥  ·Q  𝑦 )  ∧  𝑢  =  ( 𝑓  ·Q  𝑧 ) )  ∧  𝑤  =  ( 𝑣  +Q  𝑢 ) )  →  𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) | 
						
							| 23 | 22 | exp4b | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  ∧  ( 𝑓  ∈  𝐴  ∧  𝑧  ∈  𝐶 ) )  →  ( ( 𝑣  =  ( 𝑥  ·Q  𝑦 )  ∧  𝑢  =  ( 𝑓  ·Q  𝑧 ) )  →  ( 𝑤  =  ( 𝑣  +Q  𝑢 )  →  𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) ) ) | 
						
							| 24 | 23 | com3l | ⊢ ( ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  ∧  ( 𝑓  ∈  𝐴  ∧  𝑧  ∈  𝐶 ) )  →  ( ( 𝑣  =  ( 𝑥  ·Q  𝑦 )  ∧  𝑢  =  ( 𝑓  ·Q  𝑧 ) )  →  ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( 𝑤  =  ( 𝑣  +Q  𝑢 )  →  𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) ) ) | 
						
							| 25 | 24 | exp4b | ⊢ ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  →  ( ( 𝑓  ∈  𝐴  ∧  𝑧  ∈  𝐶 )  →  ( 𝑣  =  ( 𝑥  ·Q  𝑦 )  →  ( 𝑢  =  ( 𝑓  ·Q  𝑧 )  →  ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( 𝑤  =  ( 𝑣  +Q  𝑢 )  →  𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) ) ) ) ) | 
						
							| 26 | 25 | com23 | ⊢ ( ( 𝑥  ∈  𝐴  ∧  𝑦  ∈  𝐵 )  →  ( 𝑣  =  ( 𝑥  ·Q  𝑦 )  →  ( ( 𝑓  ∈  𝐴  ∧  𝑧  ∈  𝐶 )  →  ( 𝑢  =  ( 𝑓  ·Q  𝑧 )  →  ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( 𝑤  =  ( 𝑣  +Q  𝑢 )  →  𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) ) ) ) ) | 
						
							| 27 | 26 | rexlimivv | ⊢ ( ∃ 𝑥  ∈  𝐴 ∃ 𝑦  ∈  𝐵 𝑣  =  ( 𝑥  ·Q  𝑦 )  →  ( ( 𝑓  ∈  𝐴  ∧  𝑧  ∈  𝐶 )  →  ( 𝑢  =  ( 𝑓  ·Q  𝑧 )  →  ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( 𝑤  =  ( 𝑣  +Q  𝑢 )  →  𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) ) ) ) | 
						
							| 28 | 27 | rexlimdvv | ⊢ ( ∃ 𝑥  ∈  𝐴 ∃ 𝑦  ∈  𝐵 𝑣  =  ( 𝑥  ·Q  𝑦 )  →  ( ∃ 𝑓  ∈  𝐴 ∃ 𝑧  ∈  𝐶 𝑢  =  ( 𝑓  ·Q  𝑧 )  →  ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( 𝑤  =  ( 𝑣  +Q  𝑢 )  →  𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) ) ) | 
						
							| 29 | 28 | com3r | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( ∃ 𝑥  ∈  𝐴 ∃ 𝑦  ∈  𝐵 𝑣  =  ( 𝑥  ·Q  𝑦 )  →  ( ∃ 𝑓  ∈  𝐴 ∃ 𝑧  ∈  𝐶 𝑢  =  ( 𝑓  ·Q  𝑧 )  →  ( 𝑤  =  ( 𝑣  +Q  𝑢 )  →  𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) ) ) | 
						
							| 30 | 15 29 | sylbid | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( 𝑣  ∈  ( 𝐴  ·P  𝐵 )  →  ( ∃ 𝑓  ∈  𝐴 ∃ 𝑧  ∈  𝐶 𝑢  =  ( 𝑓  ·Q  𝑧 )  →  ( 𝑤  =  ( 𝑣  +Q  𝑢 )  →  𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) ) ) | 
						
							| 31 | 30 | impd | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( ( 𝑣  ∈  ( 𝐴  ·P  𝐵 )  ∧  ∃ 𝑓  ∈  𝐴 ∃ 𝑧  ∈  𝐶 𝑢  =  ( 𝑓  ·Q  𝑧 ) )  →  ( 𝑤  =  ( 𝑣  +Q  𝑢 )  →  𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) ) | 
						
							| 32 | 12 31 | sylbid | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( ( 𝑣  ∈  ( 𝐴  ·P  𝐵 )  ∧  𝑢  ∈  ( 𝐴  ·P  𝐶 ) )  →  ( 𝑤  =  ( 𝑣  +Q  𝑢 )  →  𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) ) | 
						
							| 33 | 32 | rexlimdvv | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( ∃ 𝑣  ∈  ( 𝐴  ·P  𝐵 ) ∃ 𝑢  ∈  ( 𝐴  ·P  𝐶 ) 𝑤  =  ( 𝑣  +Q  𝑢 )  →  𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) | 
						
							| 34 | 7 33 | sylbid | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( 𝑤  ∈  ( ( 𝐴  ·P  𝐵 )  +P  ( 𝐴  ·P  𝐶 ) )  →  𝑤  ∈  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) ) | 
						
							| 35 | 34 | ssrdv | ⊢ ( ( 𝐴  ∈  P  ∧  𝐵  ∈  P  ∧  𝐶  ∈  P )  →  ( ( 𝐴  ·P  𝐵 )  +P  ( 𝐴  ·P  𝐶 ) )  ⊆  ( 𝐴  ·P  ( 𝐵  +P  𝐶 ) ) ) |