| Step | Hyp | Ref | Expression | 
						
							| 1 |  | tgpcn.j | ⊢ 𝐽  =  ( TopOpen ‘ 𝐺 ) | 
						
							| 2 |  | cnmpt1plusg.p | ⊢  +   =  ( +g ‘ 𝐺 ) | 
						
							| 3 |  | cnmpt1plusg.g | ⊢ ( 𝜑  →  𝐺  ∈  TopMnd ) | 
						
							| 4 |  | cnmpt1plusg.k | ⊢ ( 𝜑  →  𝐾  ∈  ( TopOn ‘ 𝑋 ) ) | 
						
							| 5 |  | cnmpt1plusg.a | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝑋  ↦  𝐴 )  ∈  ( 𝐾  Cn  𝐽 ) ) | 
						
							| 6 |  | cnmpt1plusg.b | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝑋  ↦  𝐵 )  ∈  ( 𝐾  Cn  𝐽 ) ) | 
						
							| 7 |  | eqid | ⊢ ( Base ‘ 𝐺 )  =  ( Base ‘ 𝐺 ) | 
						
							| 8 | 1 7 | tmdtopon | ⊢ ( 𝐺  ∈  TopMnd  →  𝐽  ∈  ( TopOn ‘ ( Base ‘ 𝐺 ) ) ) | 
						
							| 9 | 3 8 | syl | ⊢ ( 𝜑  →  𝐽  ∈  ( TopOn ‘ ( Base ‘ 𝐺 ) ) ) | 
						
							| 10 |  | cnf2 | ⊢ ( ( 𝐾  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐽  ∈  ( TopOn ‘ ( Base ‘ 𝐺 ) )  ∧  ( 𝑥  ∈  𝑋  ↦  𝐴 )  ∈  ( 𝐾  Cn  𝐽 ) )  →  ( 𝑥  ∈  𝑋  ↦  𝐴 ) : 𝑋 ⟶ ( Base ‘ 𝐺 ) ) | 
						
							| 11 | 4 9 5 10 | syl3anc | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝑋  ↦  𝐴 ) : 𝑋 ⟶ ( Base ‘ 𝐺 ) ) | 
						
							| 12 | 11 | fvmptelcdm | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝑋 )  →  𝐴  ∈  ( Base ‘ 𝐺 ) ) | 
						
							| 13 |  | cnf2 | ⊢ ( ( 𝐾  ∈  ( TopOn ‘ 𝑋 )  ∧  𝐽  ∈  ( TopOn ‘ ( Base ‘ 𝐺 ) )  ∧  ( 𝑥  ∈  𝑋  ↦  𝐵 )  ∈  ( 𝐾  Cn  𝐽 ) )  →  ( 𝑥  ∈  𝑋  ↦  𝐵 ) : 𝑋 ⟶ ( Base ‘ 𝐺 ) ) | 
						
							| 14 | 4 9 6 13 | syl3anc | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝑋  ↦  𝐵 ) : 𝑋 ⟶ ( Base ‘ 𝐺 ) ) | 
						
							| 15 | 14 | fvmptelcdm | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝑋 )  →  𝐵  ∈  ( Base ‘ 𝐺 ) ) | 
						
							| 16 |  | eqid | ⊢ ( +𝑓 ‘ 𝐺 )  =  ( +𝑓 ‘ 𝐺 ) | 
						
							| 17 | 7 2 16 | plusfval | ⊢ ( ( 𝐴  ∈  ( Base ‘ 𝐺 )  ∧  𝐵  ∈  ( Base ‘ 𝐺 ) )  →  ( 𝐴 ( +𝑓 ‘ 𝐺 ) 𝐵 )  =  ( 𝐴  +  𝐵 ) ) | 
						
							| 18 | 12 15 17 | syl2anc | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝑋 )  →  ( 𝐴 ( +𝑓 ‘ 𝐺 ) 𝐵 )  =  ( 𝐴  +  𝐵 ) ) | 
						
							| 19 | 18 | mpteq2dva | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝑋  ↦  ( 𝐴 ( +𝑓 ‘ 𝐺 ) 𝐵 ) )  =  ( 𝑥  ∈  𝑋  ↦  ( 𝐴  +  𝐵 ) ) ) | 
						
							| 20 | 1 16 | tmdcn | ⊢ ( 𝐺  ∈  TopMnd  →  ( +𝑓 ‘ 𝐺 )  ∈  ( ( 𝐽  ×t  𝐽 )  Cn  𝐽 ) ) | 
						
							| 21 | 3 20 | syl | ⊢ ( 𝜑  →  ( +𝑓 ‘ 𝐺 )  ∈  ( ( 𝐽  ×t  𝐽 )  Cn  𝐽 ) ) | 
						
							| 22 | 4 5 6 21 | cnmpt12f | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝑋  ↦  ( 𝐴 ( +𝑓 ‘ 𝐺 ) 𝐵 ) )  ∈  ( 𝐾  Cn  𝐽 ) ) | 
						
							| 23 | 19 22 | eqeltrrd | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝑋  ↦  ( 𝐴  +  𝐵 ) )  ∈  ( 𝐾  Cn  𝐽 ) ) |