| Step | Hyp | Ref | Expression | 
						
							| 1 |  | rgspnval.r |  | 
						
							| 2 |  | rgspnval.b |  | 
						
							| 3 |  | rgspnval.ss |  | 
						
							| 4 |  | rgspnval.n |  | 
						
							| 5 |  | rgspnval.sp |  | 
						
							| 6 | 4 | fveq1d |  | 
						
							| 7 |  | elex |  | 
						
							| 8 |  | fveq2 |  | 
						
							| 9 | 8 | pweqd |  | 
						
							| 10 |  | fveq2 |  | 
						
							| 11 |  | rabeq |  | 
						
							| 12 | 10 11 | syl |  | 
						
							| 13 | 12 | inteqd |  | 
						
							| 14 | 9 13 | mpteq12dv |  | 
						
							| 15 |  | df-rgspn |  | 
						
							| 16 |  | fvex |  | 
						
							| 17 | 16 | pwex |  | 
						
							| 18 | 17 | mptex |  | 
						
							| 19 | 14 15 18 | fvmpt |  | 
						
							| 20 | 1 7 19 | 3syl |  | 
						
							| 21 | 20 | fveq1d |  | 
						
							| 22 |  | eqid |  | 
						
							| 23 |  | sseq1 |  | 
						
							| 24 | 23 | rabbidv |  | 
						
							| 25 | 24 | inteqd |  | 
						
							| 26 | 3 2 | sseqtrd |  | 
						
							| 27 | 16 | elpw2 |  | 
						
							| 28 | 26 27 | sylibr |  | 
						
							| 29 |  | eqid |  | 
						
							| 30 | 29 | subrgid |  | 
						
							| 31 | 1 30 | syl |  | 
						
							| 32 | 2 31 | eqeltrd |  | 
						
							| 33 |  | sseq2 |  | 
						
							| 34 | 33 | rspcev |  | 
						
							| 35 | 32 3 34 | syl2anc |  | 
						
							| 36 |  | intexrab |  | 
						
							| 37 | 35 36 | sylib |  | 
						
							| 38 | 22 25 28 37 | fvmptd3 |  | 
						
							| 39 | 21 38 | eqtrd |  | 
						
							| 40 | 5 6 39 | 3eqtrd |  |