Database REAL AND COMPLEX NUMBERS Elementary limits and convergence Finite and infinite products Finite products fprodreclf  
				
		 
		
			
		 
		Description:   Closure of a finite product of real numbers.  A version of fprodrecl  using bound-variable hypotheses instead of distinct variable conditions.
       (Contributed by Glauco Siliprandi , 5-Apr-2020) 
		
			
				
					Ref 
					Expression 
				 
					
						Hypotheses 
						fprodreclf.kph ⊢  Ⅎ 𝑘  𝜑   
					
						fprodcl.a ⊢  ( 𝜑   →  𝐴   ∈  Fin )  
					
						fprodrecl.b ⊢  ( ( 𝜑   ∧  𝑘   ∈  𝐴  )  →  𝐵   ∈  ℝ )  
				
					Assertion 
					fprodreclf ⊢   ( 𝜑   →  ∏ 𝑘   ∈  𝐴  𝐵   ∈  ℝ )  
			
		 
		
				Proof 
				
					
						Step 
						Hyp 
						Ref 
						Expression 
					 
						
							1 
								
							 
							fprodreclf.kph ⊢  Ⅎ 𝑘  𝜑   
						
							2 
								
							 
							fprodcl.a ⊢  ( 𝜑   →  𝐴   ∈  Fin )  
						
							3 
								
							 
							fprodrecl.b ⊢  ( ( 𝜑   ∧  𝑘   ∈  𝐴  )  →  𝐵   ∈  ℝ )  
						
							4 
								
							 
							ax-resscn ⊢  ℝ  ⊆  ℂ  
						
							5 
								4 
							 
							a1i ⊢  ( 𝜑   →  ℝ  ⊆  ℂ )  
						
							6 
								
							 
							remulcl ⊢  ( ( 𝑥   ∈  ℝ  ∧  𝑦   ∈  ℝ )  →  ( 𝑥   ·  𝑦  )  ∈  ℝ )  
						
							7 
								6 
							 
							adantl ⊢  ( ( 𝜑   ∧  ( 𝑥   ∈  ℝ  ∧  𝑦   ∈  ℝ ) )  →  ( 𝑥   ·  𝑦  )  ∈  ℝ )  
						
							8 
								
							 
							1red ⊢  ( 𝜑   →  1  ∈  ℝ )  
						
							9 
								1  5  7  2  3  8 
							 
							fprodcllemf ⊢  ( 𝜑   →  ∏ 𝑘   ∈  𝐴  𝐵   ∈  ℝ )