Metamath Proof Explorer
		
		
		
		Description:  Relationship between surreal division and multiplication.  (Contributed by Scott Fenton, 16-Mar-2025)
		
			
				
					|  |  | Ref | Expression | 
					
						|  | Hypotheses | divsmuld.1 | ⊢ ( 𝜑  →  𝐴  ∈   No  ) | 
					
						|  |  | divsmuld.2 | ⊢ ( 𝜑  →  𝐵  ∈   No  ) | 
					
						|  |  | divsmuld.3 | ⊢ ( 𝜑  →  𝐶  ∈   No  ) | 
					
						|  |  | divsmuld.4 | ⊢ ( 𝜑  →  𝐶  ≠   0s  ) | 
				
					|  | Assertion | divsmuld | ⊢  ( 𝜑  →  ( ( 𝐴  /su  𝐶 )  =  𝐵  ↔  ( 𝐶  ·s  𝐵 )  =  𝐴 ) ) | 
			
		
		
			
				Proof
				
					
						| Step | Hyp | Ref | Expression | 
						
							| 1 |  | divsmuld.1 | ⊢ ( 𝜑  →  𝐴  ∈   No  ) | 
						
							| 2 |  | divsmuld.2 | ⊢ ( 𝜑  →  𝐵  ∈   No  ) | 
						
							| 3 |  | divsmuld.3 | ⊢ ( 𝜑  →  𝐶  ∈   No  ) | 
						
							| 4 |  | divsmuld.4 | ⊢ ( 𝜑  →  𝐶  ≠   0s  ) | 
						
							| 5 | 3 4 | recsexd | ⊢ ( 𝜑  →  ∃ 𝑥  ∈   No  ( 𝐶  ·s  𝑥 )  =   1s  ) | 
						
							| 6 | 1 2 3 4 5 | divsmulwd | ⊢ ( 𝜑  →  ( ( 𝐴  /su  𝐶 )  =  𝐵  ↔  ( 𝐶  ·s  𝐵 )  =  𝐴 ) ) |