Database BASIC ALGEBRAIC STRUCTURES Rings Ring homomorphisms rimrhmOLD  
				
		 
		
			
		 
		Description:   Obsolete version of rimrhm  as of 12-Jan-2025.  (Contributed by AV , 22-Oct-2019)   (Proof modification is discouraged.) 
       (New usage is discouraged.) 
		
			
				
					Ref 
					Expression 
				 
					
						Hypotheses 
						rhmf1o.b   ⊢   B  =  Base  R      
					 
					
						rhmf1o.c   ⊢   C  =  Base  S      
					 
				
					Assertion 
					rimrhmOLD    ⊢   F  ∈  R   RingIso   S   →   F  ∈  R   RingHom   S        
				 
			
		 
		
				Proof 
				
					
						Step 
						Hyp 
						Ref 
						Expression 
					 
						
							1 
								
							 
							rhmf1o.b  ⊢   B  =  Base  R      
						
							2 
								
							 
							rhmf1o.c  ⊢   C  =  Base  S      
						
							3 
								1  2 
							 
							isrim   ⊢   F  ∈  R   RingIso   S   ↔    F  ∈  R   RingHom   S   ∧   F  :  B  ⟶  1-1 onto C          
						
							4 
								3 
							 
							simplbi   ⊢   F  ∈  R   RingIso   S   →   F  ∈  R   RingHom   S