Metamath Proof Explorer


Theorem sn-iotaex

Description: iotaex without ax-10 , ax-11 , ax-12 . (Contributed by SN, 6-Nov-2024)

Ref Expression
Assertion sn-iotaex
|- ( iota x ph ) e. _V

Proof

Step Hyp Ref Expression
1 sn-iotaval
 |-  ( { x | ph } = { y } -> ( iota x ph ) = y )
2 vex
 |-  y e. _V
3 1 2 eqeltrdi
 |-  ( { x | ph } = { y } -> ( iota x ph ) e. _V )
4 3 exlimiv
 |-  ( E. y { x | ph } = { y } -> ( iota x ph ) e. _V )
5 sn-iotanul
 |-  ( -. E. y { x | ph } = { y } -> ( iota x ph ) = (/) )
6 0ex
 |-  (/) e. _V
7 5 6 eqeltrdi
 |-  ( -. E. y { x | ph } = { y } -> ( iota x ph ) e. _V )
8 4 7 pm2.61i
 |-  ( iota x ph ) e. _V