Metamath Proof Explorer


Theorem iihalf2cn

Description: The second half function is a continuous map. (Contributed by Mario Carneiro, 6-Jun-2014)

Ref Expression
Hypothesis iihalf2cn.1 J = topGen ran . 𝑡 1 2 1
Assertion iihalf2cn x 1 2 1 2 x 1 J Cn II

Proof

Step Hyp Ref Expression
1 iihalf2cn.1 J = topGen ran . 𝑡 1 2 1
2 eqid TopOpen fld = TopOpen fld
3 dfii2 II = topGen ran . 𝑡 0 1
4 halfre 1 2
5 1re 1
6 iccssre 1 2 1 1 2 1
7 4 5 6 mp2an 1 2 1
8 7 a1i 1 2 1
9 unitssre 0 1
10 9 a1i 0 1
11 iihalf2 x 1 2 1 2 x 1 0 1
12 11 adantl x 1 2 1 2 x 1 0 1
13 2 cnfldtopon TopOpen fld TopOn
14 13 a1i TopOpen fld TopOn
15 2cnd 2
16 14 14 15 cnmptc x 2 TopOpen fld Cn TopOpen fld
17 14 cnmptid x x TopOpen fld Cn TopOpen fld
18 2 mulcn × TopOpen fld × t TopOpen fld Cn TopOpen fld
19 18 a1i × TopOpen fld × t TopOpen fld Cn TopOpen fld
20 14 16 17 19 cnmpt12f x 2 x TopOpen fld Cn TopOpen fld
21 1cnd 1
22 14 14 21 cnmptc x 1 TopOpen fld Cn TopOpen fld
23 2 subcn TopOpen fld × t TopOpen fld Cn TopOpen fld
24 23 a1i TopOpen fld × t TopOpen fld Cn TopOpen fld
25 14 20 22 24 cnmpt12f x 2 x 1 TopOpen fld Cn TopOpen fld
26 2 1 3 8 10 12 25 cnmptre x 1 2 1 2 x 1 J Cn II
27 26 mptru x 1 2 1 2 x 1 J Cn II