Step |
Hyp |
Ref |
Expression |
1 |
|
0nonelaleb.1 |
|- ( ph -> A e. RR ) |
2 |
|
0nonelaleb.2 |
|- ( ph -> B e. RR ) |
3 |
|
0nonelaleb.3 |
|- ( ph -> 0 < A ) |
4 |
|
0nonelaleb.4 |
|- ( ph -> A <_ B ) |
5 |
|
0nonelalab.5 |
|- ( ph -> C e. ( A (,) B ) ) |
6 |
|
0red |
|- ( ph -> 0 e. RR ) |
7 |
|
elioore |
|- ( C e. ( A (,) B ) -> C e. RR ) |
8 |
5 7
|
syl |
|- ( ph -> C e. RR ) |
9 |
1
|
rexrd |
|- ( ph -> A e. RR* ) |
10 |
2
|
rexrd |
|- ( ph -> B e. RR* ) |
11 |
|
elioo2 |
|- ( ( A e. RR* /\ B e. RR* ) -> ( C e. ( A (,) B ) <-> ( C e. RR /\ A < C /\ C < B ) ) ) |
12 |
9 10 11
|
syl2anc |
|- ( ph -> ( C e. ( A (,) B ) <-> ( C e. RR /\ A < C /\ C < B ) ) ) |
13 |
5 12
|
mpbid |
|- ( ph -> ( C e. RR /\ A < C /\ C < B ) ) |
14 |
13
|
simp2d |
|- ( ph -> A < C ) |
15 |
6 1 8 3 14
|
lttrd |
|- ( ph -> 0 < C ) |
16 |
6 15
|
ltned |
|- ( ph -> 0 =/= C ) |