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 |
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 |