Metamath Proof Explorer
		
		
		
		Description:  A local ring is a nonzero ring.  (Contributed by Jim Kingdon, 20-Feb-2025)  (Revised by SN, 23-Feb-2025)
		
			
				
					|  |  | Ref | Expression | 
					
						|  | Hypotheses | lringnz.1 | ⊢  1   =  ( 1r ‘ 𝑅 ) | 
					
						|  |  | lringnz.2 | ⊢  0   =  ( 0g ‘ 𝑅 ) | 
				
					|  | Assertion | lringnz | ⊢  ( 𝑅  ∈  LRing  →   1   ≠   0  ) | 
			
		
		
			
				Proof
				
					
						| Step | Hyp | Ref | Expression | 
						
							| 1 |  | lringnz.1 | ⊢  1   =  ( 1r ‘ 𝑅 ) | 
						
							| 2 |  | lringnz.2 | ⊢  0   =  ( 0g ‘ 𝑅 ) | 
						
							| 3 |  | lringnzr | ⊢ ( 𝑅  ∈  LRing  →  𝑅  ∈  NzRing ) | 
						
							| 4 | 1 2 | nzrnz | ⊢ ( 𝑅  ∈  NzRing  →   1   ≠   0  ) | 
						
							| 5 | 3 4 | syl | ⊢ ( 𝑅  ∈  LRing  →   1   ≠   0  ) |