Metamath Proof Explorer


Theorem elixp

Description: Membership in an infinite Cartesian product. (Contributed by NM, 28-Sep-2006)

Ref Expression
Hypothesis elixp.1 FV
Assertion elixp FxABFFnAxAFxB

Proof

Step Hyp Ref Expression
1 elixp.1 FV
2 elixp2 FxABFVFFnAxAFxB
3 3anass FVFFnAxAFxBFVFFnAxAFxB
4 1 3 mpbiran FVFFnAxAFxBFFnAxAFxB
5 2 4 bitri FxABFFnAxAFxB