Metamath Proof Explorer
		
		
		
		Description:  Equality theorem for the classes of cosets by A and B ,
       deduction form.  (Contributed by Peter Mazsa, 4-Nov-2019)
		
			
				
					|  |  | Ref | Expression | 
					
						|  | Hypothesis | cosseqd.1 |  | 
				
					|  | Assertion | cosseqd |  | 
			
		
		
			
				Proof
				
					
						| Step | Hyp | Ref | Expression | 
						
							| 1 |  | cosseqd.1 |  | 
						
							| 2 |  | cosseq |  | 
						
							| 3 | 1 2 | syl |  |