| Step | Hyp | Ref | Expression | 
						
							| 1 |  | rng2idlring.r | ⊢ ( 𝜑  →  𝑅  ∈  Rng ) | 
						
							| 2 |  | rng2idlring.i | ⊢ ( 𝜑  →  𝐼  ∈  ( 2Ideal ‘ 𝑅 ) ) | 
						
							| 3 |  | rng2idlring.j | ⊢ 𝐽  =  ( 𝑅  ↾s  𝐼 ) | 
						
							| 4 |  | rng2idlring.u | ⊢ ( 𝜑  →  𝐽  ∈  Ring ) | 
						
							| 5 |  | rng2idlring.b | ⊢ 𝐵  =  ( Base ‘ 𝑅 ) | 
						
							| 6 |  | rng2idlring.t | ⊢  ·   =  ( .r ‘ 𝑅 ) | 
						
							| 7 |  | rng2idlring.1 | ⊢  1   =  ( 1r ‘ 𝐽 ) | 
						
							| 8 |  | rngqiprngim.g | ⊢  ∼   =  ( 𝑅  ~QG  𝐼 ) | 
						
							| 9 |  | rngqiprngim.q | ⊢ 𝑄  =  ( 𝑅  /s   ∼  ) | 
						
							| 10 | 1 2 3 4 5 6 7 8 9 | rngqiprnglinlem2 | ⊢ ( ( 𝜑  ∧  ( 𝐴  ∈  𝐵  ∧  𝐶  ∈  𝐵 ) )  →  [ ( 𝐴  ·  𝐶 ) ]  ∼   =  ( [ 𝐴 ]  ∼  ( .r ‘ 𝑄 ) [ 𝐶 ]  ∼  ) ) | 
						
							| 11 | 1 | anim1i | ⊢ ( ( 𝜑  ∧  ( 𝐴  ∈  𝐵  ∧  𝐶  ∈  𝐵 ) )  →  ( 𝑅  ∈  Rng  ∧  ( 𝐴  ∈  𝐵  ∧  𝐶  ∈  𝐵 ) ) ) | 
						
							| 12 |  | 3anass | ⊢ ( ( 𝑅  ∈  Rng  ∧  𝐴  ∈  𝐵  ∧  𝐶  ∈  𝐵 )  ↔  ( 𝑅  ∈  Rng  ∧  ( 𝐴  ∈  𝐵  ∧  𝐶  ∈  𝐵 ) ) ) | 
						
							| 13 | 11 12 | sylibr | ⊢ ( ( 𝜑  ∧  ( 𝐴  ∈  𝐵  ∧  𝐶  ∈  𝐵 ) )  →  ( 𝑅  ∈  Rng  ∧  𝐴  ∈  𝐵  ∧  𝐶  ∈  𝐵 ) ) | 
						
							| 14 | 5 6 | rngcl | ⊢ ( ( 𝑅  ∈  Rng  ∧  𝐴  ∈  𝐵  ∧  𝐶  ∈  𝐵 )  →  ( 𝐴  ·  𝐶 )  ∈  𝐵 ) | 
						
							| 15 | 13 14 | syl | ⊢ ( ( 𝜑  ∧  ( 𝐴  ∈  𝐵  ∧  𝐶  ∈  𝐵 ) )  →  ( 𝐴  ·  𝐶 )  ∈  𝐵 ) | 
						
							| 16 |  | eqid | ⊢ ( Base ‘ 𝑄 )  =  ( Base ‘ 𝑄 ) | 
						
							| 17 | 8 9 5 16 | quseccl0 | ⊢ ( ( 𝑅  ∈  Rng  ∧  ( 𝐴  ·  𝐶 )  ∈  𝐵 )  →  [ ( 𝐴  ·  𝐶 ) ]  ∼   ∈  ( Base ‘ 𝑄 ) ) | 
						
							| 18 | 1 15 17 | syl2an2r | ⊢ ( ( 𝜑  ∧  ( 𝐴  ∈  𝐵  ∧  𝐶  ∈  𝐵 ) )  →  [ ( 𝐴  ·  𝐶 ) ]  ∼   ∈  ( Base ‘ 𝑄 ) ) | 
						
							| 19 | 10 18 | eqeltrrd | ⊢ ( ( 𝜑  ∧  ( 𝐴  ∈  𝐵  ∧  𝐶  ∈  𝐵 ) )  →  ( [ 𝐴 ]  ∼  ( .r ‘ 𝑄 ) [ 𝐶 ]  ∼  )  ∈  ( Base ‘ 𝑄 ) ) |