Metamath Proof Explorer
		
		
		
		Description:  The function value of an endofunction.  (Contributed by AV, 27-Jan-2024)
		
			
				
					|  |  | Ref | Expression | 
					
						|  | Hypotheses | efmndbas.g | ⊢ 𝐺  =  ( EndoFMnd ‘ 𝐴 ) | 
					
						|  |  | efmndbas.b | ⊢ 𝐵  =  ( Base ‘ 𝐺 ) | 
				
					|  | Assertion | efmndfv | ⊢  ( ( 𝐹  ∈  𝐵  ∧  𝑋  ∈  𝐴 )  →  ( 𝐹 ‘ 𝑋 )  ∈  𝐴 ) | 
			
		
		
			
				Proof
				
					
						| Step | Hyp | Ref | Expression | 
						
							| 1 |  | efmndbas.g | ⊢ 𝐺  =  ( EndoFMnd ‘ 𝐴 ) | 
						
							| 2 |  | efmndbas.b | ⊢ 𝐵  =  ( Base ‘ 𝐺 ) | 
						
							| 3 | 1 2 | efmndbasf | ⊢ ( 𝐹  ∈  𝐵  →  𝐹 : 𝐴 ⟶ 𝐴 ) | 
						
							| 4 | 3 | ffvelcdmda | ⊢ ( ( 𝐹  ∈  𝐵  ∧  𝑋  ∈  𝐴 )  →  ( 𝐹 ‘ 𝑋 )  ∈  𝐴 ) |