| Step | Hyp | Ref | Expression | 
						
							| 1 |  | neg1cn | ⊢ - 1  ∈  ℂ | 
						
							| 2 |  | hvmulcl | ⊢ ( ( - 1  ∈  ℂ  ∧  𝐶  ∈   ℋ )  →  ( - 1  ·ℎ  𝐶 )  ∈   ℋ ) | 
						
							| 3 | 1 2 | mpan | ⊢ ( 𝐶  ∈   ℋ  →  ( - 1  ·ℎ  𝐶 )  ∈   ℋ ) | 
						
							| 4 |  | ax-hvdistr1 | ⊢ ( ( 𝐴  ∈  ℂ  ∧  𝐵  ∈   ℋ  ∧  ( - 1  ·ℎ  𝐶 )  ∈   ℋ )  →  ( 𝐴  ·ℎ  ( 𝐵  +ℎ  ( - 1  ·ℎ  𝐶 ) ) )  =  ( ( 𝐴  ·ℎ  𝐵 )  +ℎ  ( 𝐴  ·ℎ  ( - 1  ·ℎ  𝐶 ) ) ) ) | 
						
							| 5 | 3 4 | syl3an3 | ⊢ ( ( 𝐴  ∈  ℂ  ∧  𝐵  ∈   ℋ  ∧  𝐶  ∈   ℋ )  →  ( 𝐴  ·ℎ  ( 𝐵  +ℎ  ( - 1  ·ℎ  𝐶 ) ) )  =  ( ( 𝐴  ·ℎ  𝐵 )  +ℎ  ( 𝐴  ·ℎ  ( - 1  ·ℎ  𝐶 ) ) ) ) | 
						
							| 6 |  | hvmulcom | ⊢ ( ( 𝐴  ∈  ℂ  ∧  - 1  ∈  ℂ  ∧  𝐶  ∈   ℋ )  →  ( 𝐴  ·ℎ  ( - 1  ·ℎ  𝐶 ) )  =  ( - 1  ·ℎ  ( 𝐴  ·ℎ  𝐶 ) ) ) | 
						
							| 7 | 1 6 | mp3an2 | ⊢ ( ( 𝐴  ∈  ℂ  ∧  𝐶  ∈   ℋ )  →  ( 𝐴  ·ℎ  ( - 1  ·ℎ  𝐶 ) )  =  ( - 1  ·ℎ  ( 𝐴  ·ℎ  𝐶 ) ) ) | 
						
							| 8 | 7 | oveq2d | ⊢ ( ( 𝐴  ∈  ℂ  ∧  𝐶  ∈   ℋ )  →  ( ( 𝐴  ·ℎ  𝐵 )  +ℎ  ( 𝐴  ·ℎ  ( - 1  ·ℎ  𝐶 ) ) )  =  ( ( 𝐴  ·ℎ  𝐵 )  +ℎ  ( - 1  ·ℎ  ( 𝐴  ·ℎ  𝐶 ) ) ) ) | 
						
							| 9 | 8 | 3adant2 | ⊢ ( ( 𝐴  ∈  ℂ  ∧  𝐵  ∈   ℋ  ∧  𝐶  ∈   ℋ )  →  ( ( 𝐴  ·ℎ  𝐵 )  +ℎ  ( 𝐴  ·ℎ  ( - 1  ·ℎ  𝐶 ) ) )  =  ( ( 𝐴  ·ℎ  𝐵 )  +ℎ  ( - 1  ·ℎ  ( 𝐴  ·ℎ  𝐶 ) ) ) ) | 
						
							| 10 | 5 9 | eqtrd | ⊢ ( ( 𝐴  ∈  ℂ  ∧  𝐵  ∈   ℋ  ∧  𝐶  ∈   ℋ )  →  ( 𝐴  ·ℎ  ( 𝐵  +ℎ  ( - 1  ·ℎ  𝐶 ) ) )  =  ( ( 𝐴  ·ℎ  𝐵 )  +ℎ  ( - 1  ·ℎ  ( 𝐴  ·ℎ  𝐶 ) ) ) ) | 
						
							| 11 |  | hvsubval | ⊢ ( ( 𝐵  ∈   ℋ  ∧  𝐶  ∈   ℋ )  →  ( 𝐵  −ℎ  𝐶 )  =  ( 𝐵  +ℎ  ( - 1  ·ℎ  𝐶 ) ) ) | 
						
							| 12 | 11 | 3adant1 | ⊢ ( ( 𝐴  ∈  ℂ  ∧  𝐵  ∈   ℋ  ∧  𝐶  ∈   ℋ )  →  ( 𝐵  −ℎ  𝐶 )  =  ( 𝐵  +ℎ  ( - 1  ·ℎ  𝐶 ) ) ) | 
						
							| 13 | 12 | oveq2d | ⊢ ( ( 𝐴  ∈  ℂ  ∧  𝐵  ∈   ℋ  ∧  𝐶  ∈   ℋ )  →  ( 𝐴  ·ℎ  ( 𝐵  −ℎ  𝐶 ) )  =  ( 𝐴  ·ℎ  ( 𝐵  +ℎ  ( - 1  ·ℎ  𝐶 ) ) ) ) | 
						
							| 14 |  | hvmulcl | ⊢ ( ( 𝐴  ∈  ℂ  ∧  𝐵  ∈   ℋ )  →  ( 𝐴  ·ℎ  𝐵 )  ∈   ℋ ) | 
						
							| 15 | 14 | 3adant3 | ⊢ ( ( 𝐴  ∈  ℂ  ∧  𝐵  ∈   ℋ  ∧  𝐶  ∈   ℋ )  →  ( 𝐴  ·ℎ  𝐵 )  ∈   ℋ ) | 
						
							| 16 |  | hvmulcl | ⊢ ( ( 𝐴  ∈  ℂ  ∧  𝐶  ∈   ℋ )  →  ( 𝐴  ·ℎ  𝐶 )  ∈   ℋ ) | 
						
							| 17 | 16 | 3adant2 | ⊢ ( ( 𝐴  ∈  ℂ  ∧  𝐵  ∈   ℋ  ∧  𝐶  ∈   ℋ )  →  ( 𝐴  ·ℎ  𝐶 )  ∈   ℋ ) | 
						
							| 18 |  | hvsubval | ⊢ ( ( ( 𝐴  ·ℎ  𝐵 )  ∈   ℋ  ∧  ( 𝐴  ·ℎ  𝐶 )  ∈   ℋ )  →  ( ( 𝐴  ·ℎ  𝐵 )  −ℎ  ( 𝐴  ·ℎ  𝐶 ) )  =  ( ( 𝐴  ·ℎ  𝐵 )  +ℎ  ( - 1  ·ℎ  ( 𝐴  ·ℎ  𝐶 ) ) ) ) | 
						
							| 19 | 15 17 18 | syl2anc | ⊢ ( ( 𝐴  ∈  ℂ  ∧  𝐵  ∈   ℋ  ∧  𝐶  ∈   ℋ )  →  ( ( 𝐴  ·ℎ  𝐵 )  −ℎ  ( 𝐴  ·ℎ  𝐶 ) )  =  ( ( 𝐴  ·ℎ  𝐵 )  +ℎ  ( - 1  ·ℎ  ( 𝐴  ·ℎ  𝐶 ) ) ) ) | 
						
							| 20 | 10 13 19 | 3eqtr4d | ⊢ ( ( 𝐴  ∈  ℂ  ∧  𝐵  ∈   ℋ  ∧  𝐶  ∈   ℋ )  →  ( 𝐴  ·ℎ  ( 𝐵  −ℎ  𝐶 ) )  =  ( ( 𝐴  ·ℎ  𝐵 )  −ℎ  ( 𝐴  ·ℎ  𝐶 ) ) ) |