Metamath Proof Explorer


Theorem bj-pinftynminfty

Description: The extended complex numbers pinfty and minfty are different. (Contributed by BJ, 27-Jun-2019)

Ref Expression
Assertion bj-pinftynminfty +∞ -∞

Proof

Step Hyp Ref Expression
1 pire π
2 pipos 0 < π
3 1 2 gt0ne0ii π 0
4 3 nesymi ¬ 0 = π
5 1 renegcli π
6 5 rexri π *
7 0red π * π 0
8 lt0neg2 π 0 < π π < 0
9 1 8 ax-mp 0 < π π < 0
10 2 9 mpbi π < 0
11 10 a1i π * π π < 0
12 0re 0
13 12 1 2 ltleii 0 π
14 13 a1i π * π 0 π
15 elioc2 π * π 0 π π 0 π < 0 0 π
16 7 11 14 15 mpbir3and π * π 0 π π
17 6 1 16 mp2an 0 π π
18 simpr π * π π
19 5 12 1 lttri π < 0 0 < π π < π
20 10 2 19 mp2an π < π
21 20 a1i π * π π < π
22 1 leidi π π
23 22 a1i π * π π π
24 elioc2 π * π π π π π π < π π π
25 18 21 23 24 mpbir3and π * π π π π
26 6 1 25 mp2an π π π
27 bj-inftyexpiinj 0 π π π π π 0 = π inftyexpi 0 = inftyexpi π
28 17 26 27 mp2an 0 = π inftyexpi 0 = inftyexpi π
29 4 28 mtbi ¬ inftyexpi 0 = inftyexpi π
30 df-bj-minfty -∞ = inftyexpi π
31 30 eqeq2i inftyexpi 0 = -∞ inftyexpi 0 = inftyexpi π
32 29 31 mtbir ¬ inftyexpi 0 = -∞
33 df-bj-pinfty +∞ = inftyexpi 0
34 33 eqeq1i +∞ = -∞ inftyexpi 0 = -∞
35 32 34 mtbir ¬ +∞ = -∞
36 35 neir +∞ -∞