Metamath Proof Explorer


Theorem trisecnconstr

Description: Not all angles can be trisected. (Contributed by Thierry Arnoux, 15-Nov-2025)

Ref Expression
Assertion trisecnconstr
|- -. A. o e. Constr ( o ^c ( 1 / 3 ) ) e. Constr

Proof

Step Hyp Ref Expression
1 eqid
 |-  ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) = ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) )
2 eqid
 |-  ( ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) ^c ( 1 / 3 ) ) = ( ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) ^c ( 1 / 3 ) )
3 1 2 cos9thpinconstr
 |-  ( ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) e. Constr /\ ( ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) ^c ( 1 / 3 ) ) e/ Constr )
4 3 simpri
 |-  ( ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) ^c ( 1 / 3 ) ) e/ Constr
5 4 neli
 |-  -. ( ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) ^c ( 1 / 3 ) ) e. Constr
6 3 simpli
 |-  ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) e. Constr
7 oveq1
 |-  ( o = ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) -> ( o ^c ( 1 / 3 ) ) = ( ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) ^c ( 1 / 3 ) ) )
8 7 eleq1d
 |-  ( o = ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) -> ( ( o ^c ( 1 / 3 ) ) e. Constr <-> ( ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) ^c ( 1 / 3 ) ) e. Constr ) )
9 8 rspcv
 |-  ( ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) e. Constr -> ( A. o e. Constr ( o ^c ( 1 / 3 ) ) e. Constr -> ( ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) ^c ( 1 / 3 ) ) e. Constr ) )
10 6 9 ax-mp
 |-  ( A. o e. Constr ( o ^c ( 1 / 3 ) ) e. Constr -> ( ( exp ` ( ( _i x. ( 2 x. _pi ) ) / 3 ) ) ^c ( 1 / 3 ) ) e. Constr )
11 5 10 mto
 |-  -. A. o e. Constr ( o ^c ( 1 / 3 ) ) e. Constr