Metamath Proof Explorer


Theorem tsetndxnplusgndx

Description: The slot for the topology is not the slot for the group operation in an extensible structure. Formerly part of proof for oppgtset . (Contributed by AV, 18-Oct-2024)

Ref Expression
Assertion tsetndxnplusgndx
|- ( TopSet ` ndx ) =/= ( +g ` ndx )

Proof

Step Hyp Ref Expression
1 2re
 |-  2 e. RR
2 2lt9
 |-  2 < 9
3 1 2 gtneii
 |-  9 =/= 2
4 tsetndx
 |-  ( TopSet ` ndx ) = 9
5 plusgndx
 |-  ( +g ` ndx ) = 2
6 4 5 neeq12i
 |-  ( ( TopSet ` ndx ) =/= ( +g ` ndx ) <-> 9 =/= 2 )
7 3 6 mpbir
 |-  ( TopSet ` ndx ) =/= ( +g ` ndx )