Metamath Proof Explorer


Theorem starvndxnmulrndx

Description: The slot for the involution function is not the slot for the base set in an extensible structure. Formerly part of proof for ressstarv . (Contributed by AV, 18-Oct-2024)

Ref Expression
Assertion starvndxnmulrndx ⊢ * ndx ≠ ⋅ ndx

Proof

Step Hyp Ref Expression
1 3re ⊢ 3 ∈ ℝ
2 3lt4 ⊢ 3 < 4
3 1 2 gtneii ⊢ 4 ≠ 3
4 starvndx ⊢ * ndx = 4
5 mulrndx ⊢ ⋅ ndx = 3
6 4 5 neeq12i ⊢ * ndx ≠ ⋅ ndx ↔ 4 ≠ 3
7 3 6 mpbir ⊢ * ndx ≠ ⋅ ndx