Metamath Proof Explorer
		
		
		
		Description:  Relationship between division and reciprocal.  Theorem I.9 of
         Apostol p. 18.  (Contributed by NM, 9-Feb-1995)
		
			
				
					|  |  | Ref | Expression | 
					
						|  | Hypotheses | divclz.1 | ⊢ 𝐴  ∈  ℂ | 
					
						|  |  | divclz.2 | ⊢ 𝐵  ∈  ℂ | 
					
						|  |  | divcl.3 | ⊢ 𝐵  ≠  0 | 
				
					|  | Assertion | divreci | ⊢  ( 𝐴  /  𝐵 )  =  ( 𝐴  ·  ( 1  /  𝐵 ) ) | 
			
		
		
			
				Proof
				
					
						| Step | Hyp | Ref | Expression | 
						
							| 1 |  | divclz.1 | ⊢ 𝐴  ∈  ℂ | 
						
							| 2 |  | divclz.2 | ⊢ 𝐵  ∈  ℂ | 
						
							| 3 |  | divcl.3 | ⊢ 𝐵  ≠  0 | 
						
							| 4 | 1 2 | divreczi | ⊢ ( 𝐵  ≠  0  →  ( 𝐴  /  𝐵 )  =  ( 𝐴  ·  ( 1  /  𝐵 ) ) ) | 
						
							| 5 | 3 4 | ax-mp | ⊢ ( 𝐴  /  𝐵 )  =  ( 𝐴  ·  ( 1  /  𝐵 ) ) |