let p be 5 _or_greater Prime; for z being Element of EC_WParam p
for P, Q being Element of EC_SetProjCo ((z `1),(z `2),p)
for a being Element of (GF p) st a <> 0. (GF p) & P `1_3 = a * (Q `1_3) & P `2_3 = a * (Q `2_3) & P `3_3 = a * (Q `3_3) holds
P _EQ_ Q
let z be Element of EC_WParam p; for P, Q being Element of EC_SetProjCo ((z `1),(z `2),p)
for a being Element of (GF p) st a <> 0. (GF p) & P `1_3 = a * (Q `1_3) & P `2_3 = a * (Q `2_3) & P `3_3 = a * (Q `3_3) holds
P _EQ_ Q
let P, Q be Element of EC_SetProjCo ((z `1),(z `2),p); for a being Element of (GF p) st a <> 0. (GF p) & P `1_3 = a * (Q `1_3) & P `2_3 = a * (Q `2_3) & P `3_3 = a * (Q `3_3) holds
P _EQ_ Q
let a be Element of (GF p); ( a <> 0. (GF p) & P `1_3 = a * (Q `1_3) & P `2_3 = a * (Q `2_3) & P `3_3 = a * (Q `3_3) implies P _EQ_ Q )
assume that
A1:
a <> 0. (GF p)
and
A2:
( P `1_3 = a * (Q `1_3) & P `2_3 = a * (Q `2_3) & P `3_3 = a * (Q `3_3) )
; P _EQ_ Q
reconsider PP = P, QQ = Q as Element of ProjCo (GF p) ;
A3: PP `1_3 =
a * (Q `1_3)
by A2, EC_PF_2:32
.=
a * (QQ `1_3)
by EC_PF_2:32
;
A4: PP `2_3 =
a * (Q `2_3)
by A2, EC_PF_2:32
.=
a * (QQ `2_3)
by EC_PF_2:32
;
PP `3_3 =
a * (Q `3_3)
by A2, EC_PF_2:32
.=
a * (QQ `3_3)
by EC_PF_2:32
;
hence
P _EQ_ Q
by A1, A3, A4, EC_PF_1:def 10; verum