Metamath Proof Explorer
		
		
		
		Description:  Add a zero in the higher places.  (Contributed by Mario Carneiro, 18-Feb-2014)
		
			
				
					 | 
					 | 
					Ref | 
					Expression | 
				
					
						 | 
						Hypotheses | 
						numnncl.1 | 
						⊢ 𝑇  ∈  ℕ0  | 
					
					
						 | 
						 | 
						numnncl.2 | 
						⊢ 𝐴  ∈  ℕ0  | 
					
				
					 | 
					Assertion | 
					num0h | 
					⊢  𝐴  =  ( ( 𝑇  ·  0 )  +  𝐴 )  | 
				
			
		
		
			
				Proof
				
					
						| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							numnncl.1 | 
							⊢ 𝑇  ∈  ℕ0  | 
						
						
							| 2 | 
							
								
							 | 
							numnncl.2 | 
							⊢ 𝐴  ∈  ℕ0  | 
						
						
							| 3 | 
							
								1
							 | 
							nn0cni | 
							⊢ 𝑇  ∈  ℂ  | 
						
						
							| 4 | 
							
								3
							 | 
							mul01i | 
							⊢ ( 𝑇  ·  0 )  =  0  | 
						
						
							| 5 | 
							
								4
							 | 
							oveq1i | 
							⊢ ( ( 𝑇  ·  0 )  +  𝐴 )  =  ( 0  +  𝐴 )  | 
						
						
							| 6 | 
							
								2
							 | 
							nn0cni | 
							⊢ 𝐴  ∈  ℂ  | 
						
						
							| 7 | 
							
								6
							 | 
							addlidi | 
							⊢ ( 0  +  𝐴 )  =  𝐴  | 
						
						
							| 8 | 
							
								5 7
							 | 
							eqtr2i | 
							⊢ 𝐴  =  ( ( 𝑇  ·  0 )  +  𝐴 )  |