Metamath Proof Explorer
		
		
		
		Description:  The ring multiplication operation of a subring of the field of complex
       numbers.  (Contributed by AV, 31-Jan-2020)
		
			
				
					|  |  | Ref | Expression | 
					
						|  | Hypothesis | cnfldsrngbas.r | ⊢ 𝑅  =  ( ℂfld  ↾s  𝑆 ) | 
				
					|  | Assertion | cnfldsrngmul | ⊢  ( 𝑆  ∈  𝑉  →   ·   =  ( .r ‘ 𝑅 ) ) | 
			
		
		
			
				Proof
				
					
						| Step | Hyp | Ref | Expression | 
						
							| 1 |  | cnfldsrngbas.r | ⊢ 𝑅  =  ( ℂfld  ↾s  𝑆 ) | 
						
							| 2 |  | cnfldmul | ⊢  ·   =  ( .r ‘ ℂfld ) | 
						
							| 3 | 1 2 | ressmulr | ⊢ ( 𝑆  ∈  𝑉  →   ·   =  ( .r ‘ 𝑅 ) ) |