Metamath Proof Explorer
		
		
		
		Description:  The logarithm of a nonzero complex number is a complex number.
       Deduction form of logcl .  (Contributed by David Moews, 28-Feb-2017)
		
			
				
					 | 
					 | 
					Ref | 
					Expression | 
				
					
						 | 
						Hypotheses | 
						logcld.1 | 
						⊢ ( 𝜑  →  𝑋  ∈  ℂ )  | 
					
					
						 | 
						 | 
						logcld.2 | 
						⊢ ( 𝜑  →  𝑋  ≠  0 )  | 
					
				
					 | 
					Assertion | 
					logcld | 
					⊢  ( 𝜑  →  ( log ‘ 𝑋 )  ∈  ℂ )  | 
				
			
		
		
			
				Proof
				
					
						| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							logcld.1 | 
							⊢ ( 𝜑  →  𝑋  ∈  ℂ )  | 
						
						
							| 2 | 
							
								
							 | 
							logcld.2 | 
							⊢ ( 𝜑  →  𝑋  ≠  0 )  | 
						
						
							| 3 | 
							
								
							 | 
							logcl | 
							⊢ ( ( 𝑋  ∈  ℂ  ∧  𝑋  ≠  0 )  →  ( log ‘ 𝑋 )  ∈  ℂ )  | 
						
						
							| 4 | 
							
								1 2 3
							 | 
							syl2anc | 
							⊢ ( 𝜑  →  ( log ‘ 𝑋 )  ∈  ℂ )  |