Metamath Proof Explorer


Theorem bj-restn0b

Description: Alternate version of bj-restn0 . (Contributed by BJ, 27-Apr-2021)

Ref Expression
Assertion bj-restn0b
|- ( ( X e. ( V \ { (/) } ) /\ A e. W ) -> ( X |`t A ) =/= (/) )

Proof

Step Hyp Ref Expression
1 eldifi
 |-  ( X e. ( V \ { (/) } ) -> X e. V )
2 eldifsni
 |-  ( X e. ( V \ { (/) } ) -> X =/= (/) )
3 1 2 jca
 |-  ( X e. ( V \ { (/) } ) -> ( X e. V /\ X =/= (/) ) )
4 3 anim1i
 |-  ( ( X e. ( V \ { (/) } ) /\ A e. W ) -> ( ( X e. V /\ X =/= (/) ) /\ A e. W ) )
5 an32
 |-  ( ( ( X e. V /\ X =/= (/) ) /\ A e. W ) <-> ( ( X e. V /\ A e. W ) /\ X =/= (/) ) )
6 4 5 sylib
 |-  ( ( X e. ( V \ { (/) } ) /\ A e. W ) -> ( ( X e. V /\ A e. W ) /\ X =/= (/) ) )
7 bj-restn0
 |-  ( ( X e. V /\ A e. W ) -> ( X =/= (/) -> ( X |`t A ) =/= (/) ) )
8 7 imp
 |-  ( ( ( X e. V /\ A e. W ) /\ X =/= (/) ) -> ( X |`t A ) =/= (/) )
9 6 8 syl
 |-  ( ( X e. ( V \ { (/) } ) /\ A e. W ) -> ( X |`t A ) =/= (/) )