| Step | Hyp | Ref | Expression | 
						
							| 1 |  | suppssof1.s |  |-  ( ph -> ( A supp Y ) C_ L ) | 
						
							| 2 |  | suppssof1.o |  |-  ( ( ph /\ v e. R ) -> ( Y O v ) = Z ) | 
						
							| 3 |  | suppssof1.a |  |-  ( ph -> A : D --> V ) | 
						
							| 4 |  | suppssof1.b |  |-  ( ph -> B : D --> R ) | 
						
							| 5 |  | suppssof1.d |  |-  ( ph -> D e. W ) | 
						
							| 6 |  | suppssof1.y |  |-  ( ph -> Y e. U ) | 
						
							| 7 | 3 | ffnd |  |-  ( ph -> A Fn D ) | 
						
							| 8 | 4 | ffnd |  |-  ( ph -> B Fn D ) | 
						
							| 9 |  | inidm |  |-  ( D i^i D ) = D | 
						
							| 10 |  | eqidd |  |-  ( ( ph /\ x e. D ) -> ( A ` x ) = ( A ` x ) ) | 
						
							| 11 |  | eqidd |  |-  ( ( ph /\ x e. D ) -> ( B ` x ) = ( B ` x ) ) | 
						
							| 12 | 7 8 5 5 9 10 11 | offval |  |-  ( ph -> ( A oF O B ) = ( x e. D |-> ( ( A ` x ) O ( B ` x ) ) ) ) | 
						
							| 13 | 12 | oveq1d |  |-  ( ph -> ( ( A oF O B ) supp Z ) = ( ( x e. D |-> ( ( A ` x ) O ( B ` x ) ) ) supp Z ) ) | 
						
							| 14 | 3 | feqmptd |  |-  ( ph -> A = ( x e. D |-> ( A ` x ) ) ) | 
						
							| 15 | 14 | oveq1d |  |-  ( ph -> ( A supp Y ) = ( ( x e. D |-> ( A ` x ) ) supp Y ) ) | 
						
							| 16 | 15 1 | eqsstrrd |  |-  ( ph -> ( ( x e. D |-> ( A ` x ) ) supp Y ) C_ L ) | 
						
							| 17 |  | fvexd |  |-  ( ( ph /\ x e. D ) -> ( A ` x ) e. _V ) | 
						
							| 18 | 4 | ffvelcdmda |  |-  ( ( ph /\ x e. D ) -> ( B ` x ) e. R ) | 
						
							| 19 | 16 2 17 18 6 | suppssov1 |  |-  ( ph -> ( ( x e. D |-> ( ( A ` x ) O ( B ` x ) ) ) supp Z ) C_ L ) | 
						
							| 20 | 13 19 | eqsstrd |  |-  ( ph -> ( ( A oF O B ) supp Z ) C_ L ) |