Metamath Proof Explorer
		
		
		
		Description:  The functional part of F is a subset of F .  (Contributed by Scott
     Fenton, 17-Apr-2014)  (Revised by Mario Carneiro, 19-Apr-2014)
		
			
				
					|  |  | Ref | Expression | 
				
					|  | Assertion | funpartss |  | 
			
		
		
			
				Proof
				
					
						| Step | Hyp | Ref | Expression | 
						
							| 1 |  | df-funpart |  | 
						
							| 2 |  | resss |  | 
						
							| 3 | 1 2 | eqsstri |  |