Metamath Proof Explorer


Theorem qdensere2

Description: QQ is dense in RR . (Contributed by NM, 24-Aug-2007)

Ref Expression
Hypotheses remet.1 𝐷 = ( ( abs ∘ − ) ↾ ( ℝ × ℝ ) )
tgioo.2 𝐽 = ( MetOpen ‘ 𝐷 )
Assertion qdensere2 ( ( cls ‘ 𝐽 ) ‘ ℚ ) = ℝ

Proof

Step Hyp Ref Expression
1 remet.1 𝐷 = ( ( abs ∘ − ) ↾ ( ℝ × ℝ ) )
2 tgioo.2 𝐽 = ( MetOpen ‘ 𝐷 )
3 1 2 tgioo ( topGen ‘ ran (,) ) = 𝐽
4 3 fveq2i ( cls ‘ ( topGen ‘ ran (,) ) ) = ( cls ‘ 𝐽 )
5 4 fveq1i ( ( cls ‘ ( topGen ‘ ran (,) ) ) ‘ ℚ ) = ( ( cls ‘ 𝐽 ) ‘ ℚ )
6 qdensere ( ( cls ‘ ( topGen ‘ ran (,) ) ) ‘ ℚ ) = ℝ
7 5 6 eqtr3i ( ( cls ‘ 𝐽 ) ‘ ℚ ) = ℝ