Metamath Proof Explorer


Theorem nqex

Description: The class of positive fractions exists. (Contributed by NM, 16-Aug-1995) (Revised by Mario Carneiro, 27-Apr-2013) (New usage is discouraged.)

Ref Expression
Assertion nqex 𝑸 V

Proof

Step Hyp Ref Expression
1 df-nq 𝑸 = y 𝑵 × 𝑵 | x 𝑵 × 𝑵 y ~ 𝑸 x ¬ 2 nd x < 𝑵 2 nd y
2 niex 𝑵 V
3 2 2 xpex 𝑵 × 𝑵 V
4 1 3 rabex2 𝑸 V