| Step | Hyp | Ref | Expression | 
						
							| 1 |  | suppofssd.1 | ⊢ ( 𝜑  →  𝐴  ∈  𝑉 ) | 
						
							| 2 |  | suppofssd.2 | ⊢ ( 𝜑  →  𝑍  ∈  𝐵 ) | 
						
							| 3 |  | suppofssd.3 | ⊢ ( 𝜑  →  𝐹 : 𝐴 ⟶ 𝐵 ) | 
						
							| 4 |  | suppofssd.4 | ⊢ ( 𝜑  →  𝐺 : 𝐴 ⟶ 𝐵 ) | 
						
							| 5 |  | suppofss2d.5 | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  ( 𝑥 𝑋 𝑍 )  =  𝑍 ) | 
						
							| 6 | 3 | ffnd | ⊢ ( 𝜑  →  𝐹  Fn  𝐴 ) | 
						
							| 7 | 4 | ffnd | ⊢ ( 𝜑  →  𝐺  Fn  𝐴 ) | 
						
							| 8 |  | inidm | ⊢ ( 𝐴  ∩  𝐴 )  =  𝐴 | 
						
							| 9 |  | eqidd | ⊢ ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  →  ( 𝐹 ‘ 𝑦 )  =  ( 𝐹 ‘ 𝑦 ) ) | 
						
							| 10 |  | eqidd | ⊢ ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  →  ( 𝐺 ‘ 𝑦 )  =  ( 𝐺 ‘ 𝑦 ) ) | 
						
							| 11 | 6 7 1 1 8 9 10 | ofval | ⊢ ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  →  ( ( 𝐹  ∘f  𝑋 𝐺 ) ‘ 𝑦 )  =  ( ( 𝐹 ‘ 𝑦 ) 𝑋 ( 𝐺 ‘ 𝑦 ) ) ) | 
						
							| 12 | 11 | adantr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  ∧  ( 𝐺 ‘ 𝑦 )  =  𝑍 )  →  ( ( 𝐹  ∘f  𝑋 𝐺 ) ‘ 𝑦 )  =  ( ( 𝐹 ‘ 𝑦 ) 𝑋 ( 𝐺 ‘ 𝑦 ) ) ) | 
						
							| 13 |  | simpr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  ∧  ( 𝐺 ‘ 𝑦 )  =  𝑍 )  →  ( 𝐺 ‘ 𝑦 )  =  𝑍 ) | 
						
							| 14 | 13 | oveq2d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  ∧  ( 𝐺 ‘ 𝑦 )  =  𝑍 )  →  ( ( 𝐹 ‘ 𝑦 ) 𝑋 ( 𝐺 ‘ 𝑦 ) )  =  ( ( 𝐹 ‘ 𝑦 ) 𝑋 𝑍 ) ) | 
						
							| 15 | 5 | ralrimiva | ⊢ ( 𝜑  →  ∀ 𝑥  ∈  𝐵 ( 𝑥 𝑋 𝑍 )  =  𝑍 ) | 
						
							| 16 | 15 | adantr | ⊢ ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  →  ∀ 𝑥  ∈  𝐵 ( 𝑥 𝑋 𝑍 )  =  𝑍 ) | 
						
							| 17 | 3 | ffvelcdmda | ⊢ ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  →  ( 𝐹 ‘ 𝑦 )  ∈  𝐵 ) | 
						
							| 18 |  | simpr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  ∧  𝑥  =  ( 𝐹 ‘ 𝑦 ) )  →  𝑥  =  ( 𝐹 ‘ 𝑦 ) ) | 
						
							| 19 | 18 | oveq1d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  ∧  𝑥  =  ( 𝐹 ‘ 𝑦 ) )  →  ( 𝑥 𝑋 𝑍 )  =  ( ( 𝐹 ‘ 𝑦 ) 𝑋 𝑍 ) ) | 
						
							| 20 | 19 | eqeq1d | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  ∧  𝑥  =  ( 𝐹 ‘ 𝑦 ) )  →  ( ( 𝑥 𝑋 𝑍 )  =  𝑍  ↔  ( ( 𝐹 ‘ 𝑦 ) 𝑋 𝑍 )  =  𝑍 ) ) | 
						
							| 21 | 17 20 | rspcdv | ⊢ ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  →  ( ∀ 𝑥  ∈  𝐵 ( 𝑥 𝑋 𝑍 )  =  𝑍  →  ( ( 𝐹 ‘ 𝑦 ) 𝑋 𝑍 )  =  𝑍 ) ) | 
						
							| 22 | 16 21 | mpd | ⊢ ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  →  ( ( 𝐹 ‘ 𝑦 ) 𝑋 𝑍 )  =  𝑍 ) | 
						
							| 23 | 22 | adantr | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  ∧  ( 𝐺 ‘ 𝑦 )  =  𝑍 )  →  ( ( 𝐹 ‘ 𝑦 ) 𝑋 𝑍 )  =  𝑍 ) | 
						
							| 24 | 12 14 23 | 3eqtrd | ⊢ ( ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  ∧  ( 𝐺 ‘ 𝑦 )  =  𝑍 )  →  ( ( 𝐹  ∘f  𝑋 𝐺 ) ‘ 𝑦 )  =  𝑍 ) | 
						
							| 25 | 24 | ex | ⊢ ( ( 𝜑  ∧  𝑦  ∈  𝐴 )  →  ( ( 𝐺 ‘ 𝑦 )  =  𝑍  →  ( ( 𝐹  ∘f  𝑋 𝐺 ) ‘ 𝑦 )  =  𝑍 ) ) | 
						
							| 26 | 25 | ralrimiva | ⊢ ( 𝜑  →  ∀ 𝑦  ∈  𝐴 ( ( 𝐺 ‘ 𝑦 )  =  𝑍  →  ( ( 𝐹  ∘f  𝑋 𝐺 ) ‘ 𝑦 )  =  𝑍 ) ) | 
						
							| 27 | 6 7 1 1 8 | offn | ⊢ ( 𝜑  →  ( 𝐹  ∘f  𝑋 𝐺 )  Fn  𝐴 ) | 
						
							| 28 |  | ssidd | ⊢ ( 𝜑  →  𝐴  ⊆  𝐴 ) | 
						
							| 29 |  | suppfnss | ⊢ ( ( ( ( 𝐹  ∘f  𝑋 𝐺 )  Fn  𝐴  ∧  𝐺  Fn  𝐴 )  ∧  ( 𝐴  ⊆  𝐴  ∧  𝐴  ∈  𝑉  ∧  𝑍  ∈  𝐵 ) )  →  ( ∀ 𝑦  ∈  𝐴 ( ( 𝐺 ‘ 𝑦 )  =  𝑍  →  ( ( 𝐹  ∘f  𝑋 𝐺 ) ‘ 𝑦 )  =  𝑍 )  →  ( ( 𝐹  ∘f  𝑋 𝐺 )  supp  𝑍 )  ⊆  ( 𝐺  supp  𝑍 ) ) ) | 
						
							| 30 | 27 7 28 1 2 29 | syl23anc | ⊢ ( 𝜑  →  ( ∀ 𝑦  ∈  𝐴 ( ( 𝐺 ‘ 𝑦 )  =  𝑍  →  ( ( 𝐹  ∘f  𝑋 𝐺 ) ‘ 𝑦 )  =  𝑍 )  →  ( ( 𝐹  ∘f  𝑋 𝐺 )  supp  𝑍 )  ⊆  ( 𝐺  supp  𝑍 ) ) ) | 
						
							| 31 | 26 30 | mpd | ⊢ ( 𝜑  →  ( ( 𝐹  ∘f  𝑋 𝐺 )  supp  𝑍 )  ⊆  ( 𝐺  supp  𝑍 ) ) |