Metamath Proof Explorer
		
		
		
		Description:  Property of the multiplicative inverse in a division ring.  ( recidd analog).  (Contributed by SN, 14-Aug-2024)
		
			
				
					|  |  | Ref | Expression | 
					
						|  | Hypotheses | drnginvrld.b | ⊢ 𝐵  =  ( Base ‘ 𝑅 ) | 
					
						|  |  | drnginvrld.0 | ⊢  0   =  ( 0g ‘ 𝑅 ) | 
					
						|  |  | drnginvrld.t | ⊢  ·   =  ( .r ‘ 𝑅 ) | 
					
						|  |  | drnginvrld.u | ⊢  1   =  ( 1r ‘ 𝑅 ) | 
					
						|  |  | drnginvrld.i | ⊢ 𝐼  =  ( invr ‘ 𝑅 ) | 
					
						|  |  | drnginvrld.r | ⊢ ( 𝜑  →  𝑅  ∈  DivRing ) | 
					
						|  |  | drnginvrld.x | ⊢ ( 𝜑  →  𝑋  ∈  𝐵 ) | 
					
						|  |  | drnginvrld.1 | ⊢ ( 𝜑  →  𝑋  ≠   0  ) | 
				
					|  | Assertion | drnginvrrd | ⊢  ( 𝜑  →  ( 𝑋  ·  ( 𝐼 ‘ 𝑋 ) )  =   1  ) | 
			
		
		
			
				Proof
				
					
						| Step | Hyp | Ref | Expression | 
						
							| 1 |  | drnginvrld.b | ⊢ 𝐵  =  ( Base ‘ 𝑅 ) | 
						
							| 2 |  | drnginvrld.0 | ⊢  0   =  ( 0g ‘ 𝑅 ) | 
						
							| 3 |  | drnginvrld.t | ⊢  ·   =  ( .r ‘ 𝑅 ) | 
						
							| 4 |  | drnginvrld.u | ⊢  1   =  ( 1r ‘ 𝑅 ) | 
						
							| 5 |  | drnginvrld.i | ⊢ 𝐼  =  ( invr ‘ 𝑅 ) | 
						
							| 6 |  | drnginvrld.r | ⊢ ( 𝜑  →  𝑅  ∈  DivRing ) | 
						
							| 7 |  | drnginvrld.x | ⊢ ( 𝜑  →  𝑋  ∈  𝐵 ) | 
						
							| 8 |  | drnginvrld.1 | ⊢ ( 𝜑  →  𝑋  ≠   0  ) | 
						
							| 9 | 1 2 3 4 5 | drnginvrr | ⊢ ( ( 𝑅  ∈  DivRing  ∧  𝑋  ∈  𝐵  ∧  𝑋  ≠   0  )  →  ( 𝑋  ·  ( 𝐼 ‘ 𝑋 ) )  =   1  ) | 
						
							| 10 | 6 7 8 9 | syl3anc | ⊢ ( 𝜑  →  ( 𝑋  ·  ( 𝐼 ‘ 𝑋 ) )  =   1  ) |