| Step | Hyp | Ref | Expression | 
						
							| 1 |  | chscl.1 |  |-  ( ph -> A e. CH ) | 
						
							| 2 |  | chscl.2 |  |-  ( ph -> B e. CH ) | 
						
							| 3 |  | chscl.3 |  |-  ( ph -> B C_ ( _|_ ` A ) ) | 
						
							| 4 |  | chscl.4 |  |-  ( ph -> H : NN --> ( A +H B ) ) | 
						
							| 5 |  | chscl.5 |  |-  ( ph -> H ~~>v u ) | 
						
							| 6 |  | chscl.6 |  |-  F = ( n e. NN |-> ( ( projh ` A ) ` ( H ` n ) ) ) | 
						
							| 7 |  | chscllem3.7 |  |-  ( ph -> N e. NN ) | 
						
							| 8 |  | chscllem3.8 |  |-  ( ph -> C e. A ) | 
						
							| 9 |  | chscllem3.9 |  |-  ( ph -> D e. B ) | 
						
							| 10 |  | chscllem3.10 |  |-  ( ph -> ( H ` N ) = ( C +h D ) ) | 
						
							| 11 |  | 2fveq3 |  |-  ( n = N -> ( ( projh ` A ) ` ( H ` n ) ) = ( ( projh ` A ) ` ( H ` N ) ) ) | 
						
							| 12 |  | fvex |  |-  ( ( projh ` A ) ` ( H ` N ) ) e. _V | 
						
							| 13 | 11 6 12 | fvmpt |  |-  ( N e. NN -> ( F ` N ) = ( ( projh ` A ) ` ( H ` N ) ) ) | 
						
							| 14 | 7 13 | syl |  |-  ( ph -> ( F ` N ) = ( ( projh ` A ) ` ( H ` N ) ) ) | 
						
							| 15 | 14 | eqcomd |  |-  ( ph -> ( ( projh ` A ) ` ( H ` N ) ) = ( F ` N ) ) | 
						
							| 16 |  | chsh |  |-  ( B e. CH -> B e. SH ) | 
						
							| 17 | 2 16 | syl |  |-  ( ph -> B e. SH ) | 
						
							| 18 |  | chsh |  |-  ( A e. CH -> A e. SH ) | 
						
							| 19 | 1 18 | syl |  |-  ( ph -> A e. SH ) | 
						
							| 20 |  | shocsh |  |-  ( A e. SH -> ( _|_ ` A ) e. SH ) | 
						
							| 21 | 19 20 | syl |  |-  ( ph -> ( _|_ ` A ) e. SH ) | 
						
							| 22 |  | shless |  |-  ( ( ( B e. SH /\ ( _|_ ` A ) e. SH /\ A e. SH ) /\ B C_ ( _|_ ` A ) ) -> ( B +H A ) C_ ( ( _|_ ` A ) +H A ) ) | 
						
							| 23 | 17 21 19 3 22 | syl31anc |  |-  ( ph -> ( B +H A ) C_ ( ( _|_ ` A ) +H A ) ) | 
						
							| 24 |  | shscom |  |-  ( ( A e. SH /\ B e. SH ) -> ( A +H B ) = ( B +H A ) ) | 
						
							| 25 | 19 17 24 | syl2anc |  |-  ( ph -> ( A +H B ) = ( B +H A ) ) | 
						
							| 26 |  | shscom |  |-  ( ( A e. SH /\ ( _|_ ` A ) e. SH ) -> ( A +H ( _|_ ` A ) ) = ( ( _|_ ` A ) +H A ) ) | 
						
							| 27 | 19 21 26 | syl2anc |  |-  ( ph -> ( A +H ( _|_ ` A ) ) = ( ( _|_ ` A ) +H A ) ) | 
						
							| 28 | 23 25 27 | 3sstr4d |  |-  ( ph -> ( A +H B ) C_ ( A +H ( _|_ ` A ) ) ) | 
						
							| 29 | 4 7 | ffvelcdmd |  |-  ( ph -> ( H ` N ) e. ( A +H B ) ) | 
						
							| 30 | 28 29 | sseldd |  |-  ( ph -> ( H ` N ) e. ( A +H ( _|_ ` A ) ) ) | 
						
							| 31 |  | pjpreeq |  |-  ( ( A e. CH /\ ( H ` N ) e. ( A +H ( _|_ ` A ) ) ) -> ( ( ( projh ` A ) ` ( H ` N ) ) = ( F ` N ) <-> ( ( F ` N ) e. A /\ E. z e. ( _|_ ` A ) ( H ` N ) = ( ( F ` N ) +h z ) ) ) ) | 
						
							| 32 | 1 30 31 | syl2anc |  |-  ( ph -> ( ( ( projh ` A ) ` ( H ` N ) ) = ( F ` N ) <-> ( ( F ` N ) e. A /\ E. z e. ( _|_ ` A ) ( H ` N ) = ( ( F ` N ) +h z ) ) ) ) | 
						
							| 33 | 15 32 | mpbid |  |-  ( ph -> ( ( F ` N ) e. A /\ E. z e. ( _|_ ` A ) ( H ` N ) = ( ( F ` N ) +h z ) ) ) | 
						
							| 34 | 33 | simprd |  |-  ( ph -> E. z e. ( _|_ ` A ) ( H ` N ) = ( ( F ` N ) +h z ) ) | 
						
							| 35 | 19 | adantr |  |-  ( ( ph /\ ( z e. ( _|_ ` A ) /\ ( H ` N ) = ( ( F ` N ) +h z ) ) ) -> A e. SH ) | 
						
							| 36 | 21 | adantr |  |-  ( ( ph /\ ( z e. ( _|_ ` A ) /\ ( H ` N ) = ( ( F ` N ) +h z ) ) ) -> ( _|_ ` A ) e. SH ) | 
						
							| 37 |  | ocin |  |-  ( A e. SH -> ( A i^i ( _|_ ` A ) ) = 0H ) | 
						
							| 38 | 19 37 | syl |  |-  ( ph -> ( A i^i ( _|_ ` A ) ) = 0H ) | 
						
							| 39 | 38 | adantr |  |-  ( ( ph /\ ( z e. ( _|_ ` A ) /\ ( H ` N ) = ( ( F ` N ) +h z ) ) ) -> ( A i^i ( _|_ ` A ) ) = 0H ) | 
						
							| 40 | 8 | adantr |  |-  ( ( ph /\ ( z e. ( _|_ ` A ) /\ ( H ` N ) = ( ( F ` N ) +h z ) ) ) -> C e. A ) | 
						
							| 41 | 3 | adantr |  |-  ( ( ph /\ ( z e. ( _|_ ` A ) /\ ( H ` N ) = ( ( F ` N ) +h z ) ) ) -> B C_ ( _|_ ` A ) ) | 
						
							| 42 | 9 | adantr |  |-  ( ( ph /\ ( z e. ( _|_ ` A ) /\ ( H ` N ) = ( ( F ` N ) +h z ) ) ) -> D e. B ) | 
						
							| 43 | 41 42 | sseldd |  |-  ( ( ph /\ ( z e. ( _|_ ` A ) /\ ( H ` N ) = ( ( F ` N ) +h z ) ) ) -> D e. ( _|_ ` A ) ) | 
						
							| 44 | 1 2 3 4 5 6 | chscllem1 |  |-  ( ph -> F : NN --> A ) | 
						
							| 45 | 44 7 | ffvelcdmd |  |-  ( ph -> ( F ` N ) e. A ) | 
						
							| 46 | 45 | adantr |  |-  ( ( ph /\ ( z e. ( _|_ ` A ) /\ ( H ` N ) = ( ( F ` N ) +h z ) ) ) -> ( F ` N ) e. A ) | 
						
							| 47 |  | simprl |  |-  ( ( ph /\ ( z e. ( _|_ ` A ) /\ ( H ` N ) = ( ( F ` N ) +h z ) ) ) -> z e. ( _|_ ` A ) ) | 
						
							| 48 | 10 | adantr |  |-  ( ( ph /\ ( z e. ( _|_ ` A ) /\ ( H ` N ) = ( ( F ` N ) +h z ) ) ) -> ( H ` N ) = ( C +h D ) ) | 
						
							| 49 |  | simprr |  |-  ( ( ph /\ ( z e. ( _|_ ` A ) /\ ( H ` N ) = ( ( F ` N ) +h z ) ) ) -> ( H ` N ) = ( ( F ` N ) +h z ) ) | 
						
							| 50 | 48 49 | eqtr3d |  |-  ( ( ph /\ ( z e. ( _|_ ` A ) /\ ( H ` N ) = ( ( F ` N ) +h z ) ) ) -> ( C +h D ) = ( ( F ` N ) +h z ) ) | 
						
							| 51 | 35 36 39 40 43 46 47 50 | shuni |  |-  ( ( ph /\ ( z e. ( _|_ ` A ) /\ ( H ` N ) = ( ( F ` N ) +h z ) ) ) -> ( C = ( F ` N ) /\ D = z ) ) | 
						
							| 52 | 51 | simpld |  |-  ( ( ph /\ ( z e. ( _|_ ` A ) /\ ( H ` N ) = ( ( F ` N ) +h z ) ) ) -> C = ( F ` N ) ) | 
						
							| 53 | 34 52 | rexlimddv |  |-  ( ph -> C = ( F ` N ) ) |