| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mrcfval.f | ⊢ 𝐹  =  ( mrCls ‘ 𝐶 ) | 
						
							| 2 |  | simp1 | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑈  ⊆  𝑋  ∧  𝑉  ⊆  𝑋 )  →  𝐶  ∈  ( Moore ‘ 𝑋 ) ) | 
						
							| 3 |  | mre1cl | ⊢ ( 𝐶  ∈  ( Moore ‘ 𝑋 )  →  𝑋  ∈  𝐶 ) | 
						
							| 4 |  | elpw2g | ⊢ ( 𝑋  ∈  𝐶  →  ( 𝑈  ∈  𝒫  𝑋  ↔  𝑈  ⊆  𝑋 ) ) | 
						
							| 5 | 3 4 | syl | ⊢ ( 𝐶  ∈  ( Moore ‘ 𝑋 )  →  ( 𝑈  ∈  𝒫  𝑋  ↔  𝑈  ⊆  𝑋 ) ) | 
						
							| 6 | 5 | biimpar | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑈  ⊆  𝑋 )  →  𝑈  ∈  𝒫  𝑋 ) | 
						
							| 7 | 6 | 3adant3 | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑈  ⊆  𝑋  ∧  𝑉  ⊆  𝑋 )  →  𝑈  ∈  𝒫  𝑋 ) | 
						
							| 8 |  | elpw2g | ⊢ ( 𝑋  ∈  𝐶  →  ( 𝑉  ∈  𝒫  𝑋  ↔  𝑉  ⊆  𝑋 ) ) | 
						
							| 9 | 3 8 | syl | ⊢ ( 𝐶  ∈  ( Moore ‘ 𝑋 )  →  ( 𝑉  ∈  𝒫  𝑋  ↔  𝑉  ⊆  𝑋 ) ) | 
						
							| 10 | 9 | biimpar | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑉  ⊆  𝑋 )  →  𝑉  ∈  𝒫  𝑋 ) | 
						
							| 11 | 10 | 3adant2 | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑈  ⊆  𝑋  ∧  𝑉  ⊆  𝑋 )  →  𝑉  ∈  𝒫  𝑋 ) | 
						
							| 12 | 7 11 | prssd | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑈  ⊆  𝑋  ∧  𝑉  ⊆  𝑋 )  →  { 𝑈 ,  𝑉 }  ⊆  𝒫  𝑋 ) | 
						
							| 13 | 1 | mrcuni | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  { 𝑈 ,  𝑉 }  ⊆  𝒫  𝑋 )  →  ( 𝐹 ‘ ∪  { 𝑈 ,  𝑉 } )  =  ( 𝐹 ‘ ∪  ( 𝐹  “  { 𝑈 ,  𝑉 } ) ) ) | 
						
							| 14 | 2 12 13 | syl2anc | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑈  ⊆  𝑋  ∧  𝑉  ⊆  𝑋 )  →  ( 𝐹 ‘ ∪  { 𝑈 ,  𝑉 } )  =  ( 𝐹 ‘ ∪  ( 𝐹  “  { 𝑈 ,  𝑉 } ) ) ) | 
						
							| 15 |  | uniprg | ⊢ ( ( 𝑈  ∈  𝒫  𝑋  ∧  𝑉  ∈  𝒫  𝑋 )  →  ∪  { 𝑈 ,  𝑉 }  =  ( 𝑈  ∪  𝑉 ) ) | 
						
							| 16 | 7 11 15 | syl2anc | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑈  ⊆  𝑋  ∧  𝑉  ⊆  𝑋 )  →  ∪  { 𝑈 ,  𝑉 }  =  ( 𝑈  ∪  𝑉 ) ) | 
						
							| 17 | 16 | fveq2d | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑈  ⊆  𝑋  ∧  𝑉  ⊆  𝑋 )  →  ( 𝐹 ‘ ∪  { 𝑈 ,  𝑉 } )  =  ( 𝐹 ‘ ( 𝑈  ∪  𝑉 ) ) ) | 
						
							| 18 | 1 | mrcf | ⊢ ( 𝐶  ∈  ( Moore ‘ 𝑋 )  →  𝐹 : 𝒫  𝑋 ⟶ 𝐶 ) | 
						
							| 19 | 18 | ffnd | ⊢ ( 𝐶  ∈  ( Moore ‘ 𝑋 )  →  𝐹  Fn  𝒫  𝑋 ) | 
						
							| 20 | 19 | 3ad2ant1 | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑈  ⊆  𝑋  ∧  𝑉  ⊆  𝑋 )  →  𝐹  Fn  𝒫  𝑋 ) | 
						
							| 21 |  | fnimapr | ⊢ ( ( 𝐹  Fn  𝒫  𝑋  ∧  𝑈  ∈  𝒫  𝑋  ∧  𝑉  ∈  𝒫  𝑋 )  →  ( 𝐹  “  { 𝑈 ,  𝑉 } )  =  { ( 𝐹 ‘ 𝑈 ) ,  ( 𝐹 ‘ 𝑉 ) } ) | 
						
							| 22 | 20 7 11 21 | syl3anc | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑈  ⊆  𝑋  ∧  𝑉  ⊆  𝑋 )  →  ( 𝐹  “  { 𝑈 ,  𝑉 } )  =  { ( 𝐹 ‘ 𝑈 ) ,  ( 𝐹 ‘ 𝑉 ) } ) | 
						
							| 23 | 22 | unieqd | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑈  ⊆  𝑋  ∧  𝑉  ⊆  𝑋 )  →  ∪  ( 𝐹  “  { 𝑈 ,  𝑉 } )  =  ∪  { ( 𝐹 ‘ 𝑈 ) ,  ( 𝐹 ‘ 𝑉 ) } ) | 
						
							| 24 |  | fvex | ⊢ ( 𝐹 ‘ 𝑈 )  ∈  V | 
						
							| 25 |  | fvex | ⊢ ( 𝐹 ‘ 𝑉 )  ∈  V | 
						
							| 26 | 24 25 | unipr | ⊢ ∪  { ( 𝐹 ‘ 𝑈 ) ,  ( 𝐹 ‘ 𝑉 ) }  =  ( ( 𝐹 ‘ 𝑈 )  ∪  ( 𝐹 ‘ 𝑉 ) ) | 
						
							| 27 | 23 26 | eqtrdi | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑈  ⊆  𝑋  ∧  𝑉  ⊆  𝑋 )  →  ∪  ( 𝐹  “  { 𝑈 ,  𝑉 } )  =  ( ( 𝐹 ‘ 𝑈 )  ∪  ( 𝐹 ‘ 𝑉 ) ) ) | 
						
							| 28 | 27 | fveq2d | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑈  ⊆  𝑋  ∧  𝑉  ⊆  𝑋 )  →  ( 𝐹 ‘ ∪  ( 𝐹  “  { 𝑈 ,  𝑉 } ) )  =  ( 𝐹 ‘ ( ( 𝐹 ‘ 𝑈 )  ∪  ( 𝐹 ‘ 𝑉 ) ) ) ) | 
						
							| 29 | 14 17 28 | 3eqtr3d | ⊢ ( ( 𝐶  ∈  ( Moore ‘ 𝑋 )  ∧  𝑈  ⊆  𝑋  ∧  𝑉  ⊆  𝑋 )  →  ( 𝐹 ‘ ( 𝑈  ∪  𝑉 ) )  =  ( 𝐹 ‘ ( ( 𝐹 ‘ 𝑈 )  ∪  ( 𝐹 ‘ 𝑉 ) ) ) ) |