set F = FAdj (F_Rat,{3-CRoot(2),zeta});
Roots (F_Complex,X^3-2) c= the carrier of (FAdj (F_Rat,{3-CRoot(2),zeta}))
proof
A1: {3-CRoot(2),zeta} is Subset of (FAdj (F_Rat,{3-CRoot(2),zeta})) by FIELD_6:35;
( 3-Root(2) in {3-CRoot(2),zeta} & zeta in {3-CRoot(2),zeta} ) by TARSKI:def 2;
then reconsider a = 3-Root(2) , b = zeta as Element of (FAdj (F_Rat,{3-CRoot(2),zeta})) by A1;
A3: FAdj (F_Rat,{3-CRoot(2),zeta}) is Subring of F_Complex by FIELD_4:def 1;
A5: zeta * zeta = b * b by A3, FIELD_6:16;
now :: thesis: for o being object st o in Roots (F_Complex,X^3-2) holds
o in the carrier of (FAdj (F_Rat,{3-CRoot(2),zeta}))
end;
hence Roots (F_Complex,X^3-2) c= the carrier of (FAdj (F_Rat,{3-CRoot(2),zeta})) ; :: thesis: verum
end;
then B: X^3-2 splits_in FAdj (F_Rat,{3-CRoot(2),zeta}) by LLsplit, FIELD_8:27;
now :: thesis: for E being FieldExtension of F_Rat st X^3-2 splits_in E & E is Subfield of FAdj (F_Rat,{3-CRoot(2),zeta}) holds
E == FAdj (F_Rat,{3-CRoot(2),zeta})
let E be FieldExtension of F_Rat ; :: thesis: ( X^3-2 splits_in E & E is Subfield of FAdj (F_Rat,{3-CRoot(2),zeta}) implies E == FAdj (F_Rat,{3-CRoot(2),zeta}) )
assume C: ( X^3-2 splits_in E & E is Subfield of FAdj (F_Rat,{3-CRoot(2),zeta}) ) ; :: thesis: E == FAdj (F_Rat,{3-CRoot(2),zeta})
then E: E is Subfield of F_Complex by EC_PF_1:5;
then F: E is Subring of F_Complex by FIELD_5:12;
D: F_Rat is Subfield of E by FIELD_4:7;
{3-CRoot(2),zeta} is Subset of E
proof end;
then FAdj (F_Rat,{3-CRoot(2),zeta}) is Subfield of E by D, E, FIELD_6:37;
hence E == FAdj (F_Rat,{3-CRoot(2),zeta}) by C, FIELD_7:def 2; :: thesis: verum
end;
hence FAdj (F_Rat,{3-CRoot(2),zeta}) is SplittingField of X^3-2 by B, FIELD_8:def 1; :: thesis: verum