let p be 5 _or_greater Prime; for z being Element of EC_WParam p
for O being Element of EC_SetProjCo ((z `1),(z `2),p) st O = [0,1,0] holds
(compell_ProjCo (z,p)) . O _EQ_ O
let z be Element of EC_WParam p; for O being Element of EC_SetProjCo ((z `1),(z `2),p) st O = [0,1,0] holds
(compell_ProjCo (z,p)) . O _EQ_ O
let O be Element of EC_SetProjCo ((z `1),(z `2),p); ( O = [0,1,0] implies (compell_ProjCo (z,p)) . O _EQ_ O )
assume A1:
O = [0,1,0]
; (compell_ProjCo (z,p)) . O _EQ_ O
set a = z `1 ;
set b = z `2 ;
A2:
( O `1_3 = 0 & O `2_3 = 1 & O `3_3 = 0 )
by A1, Def3, Def4, Def5;
consider OO being Element of ProjCo (GF p) such that
A3:
( OO = O & OO in EC_SetProjCo ((z `1),(z `2),p) )
;
A4:
( OO `1_3 = 0 & OO `2_3 = 1 & OO `3_3 = 0 )
by A2, A3, Th32;
set CO = (compell_ProjCo (z,p)) . O;
consider COO being Element of ProjCo (GF p) such that
A5:
( COO = (compell_ProjCo (z,p)) . O & COO in EC_SetProjCo ((z `1),(z `2),p) )
;
A6:
( COO `1_3 = ((compell_ProjCo (z,p)) . O) `1_3 & COO `2_3 = ((compell_ProjCo (z,p)) . O) `2_3 & COO `3_3 = ((compell_ProjCo (z,p)) . O) `3_3 )
by A5, Th32;
(compell_ProjCo (z,p)) . O = [(O `1_3),(- (O `2_3)),(O `3_3)]
by Def8;
then
COO `3_3 = 0
by A2, A6, Def5;
then A7:
rep_pt ((compell_ProjCo (z,p)) . O) = [0,1,0]
by A5, Def7;
rep_pt O = [0,1,0]
by A3, A4, Def7;
hence
(compell_ProjCo (z,p)) . O _EQ_ O
by A7, Th39; verum