Metamath Proof Explorer


Theorem eliccelioc

Description: Membership in a closed interval and in a left-open right-closed interval. (Contributed by Glauco Siliprandi, 11-Dec-2019)

Ref Expression
Hypotheses eliccelioc.a
|- ( ph -> A e. RR )
eliccelioc.b
|- ( ph -> B e. RR )
eliccelioc.c
|- ( ph -> C e. RR* )
Assertion eliccelioc
|- ( ph -> ( C e. ( A (,] B ) <-> ( C e. ( A [,] B ) /\ C =/= A ) ) )

Proof

Step Hyp Ref Expression
1 eliccelioc.a
 |-  ( ph -> A e. RR )
2 eliccelioc.b
 |-  ( ph -> B e. RR )
3 eliccelioc.c
 |-  ( ph -> C e. RR* )
4 iocssicc
 |-  ( A (,] B ) C_ ( A [,] B )
5 4 sseli
 |-  ( C e. ( A (,] B ) -> C e. ( A [,] B ) )
6 5 adantl
 |-  ( ( ph /\ C e. ( A (,] B ) ) -> C e. ( A [,] B ) )
7 1 adantr
 |-  ( ( ph /\ C e. ( A (,] B ) ) -> A e. RR )
8 1 rexrd
 |-  ( ph -> A e. RR* )
9 8 adantr
 |-  ( ( ph /\ C e. ( A (,] B ) ) -> A e. RR* )
10 2 adantr
 |-  ( ( ph /\ C e. ( A (,] B ) ) -> B e. RR )
11 10 rexrd
 |-  ( ( ph /\ C e. ( A (,] B ) ) -> B e. RR* )
12 simpr
 |-  ( ( ph /\ C e. ( A (,] B ) ) -> C e. ( A (,] B ) )
13 iocgtlb
 |-  ( ( A e. RR* /\ B e. RR* /\ C e. ( A (,] B ) ) -> A < C )
14 9 11 12 13 syl3anc
 |-  ( ( ph /\ C e. ( A (,] B ) ) -> A < C )
15 7 14 gtned
 |-  ( ( ph /\ C e. ( A (,] B ) ) -> C =/= A )
16 6 15 jca
 |-  ( ( ph /\ C e. ( A (,] B ) ) -> ( C e. ( A [,] B ) /\ C =/= A ) )
17 8 adantr
 |-  ( ( ph /\ ( C e. ( A [,] B ) /\ C =/= A ) ) -> A e. RR* )
18 2 rexrd
 |-  ( ph -> B e. RR* )
19 18 adantr
 |-  ( ( ph /\ ( C e. ( A [,] B ) /\ C =/= A ) ) -> B e. RR* )
20 3 adantr
 |-  ( ( ph /\ ( C e. ( A [,] B ) /\ C =/= A ) ) -> C e. RR* )
21 1 adantr
 |-  ( ( ph /\ ( C e. ( A [,] B ) /\ C =/= A ) ) -> A e. RR )
22 1 2 iccssred
 |-  ( ph -> ( A [,] B ) C_ RR )
23 22 sselda
 |-  ( ( ph /\ C e. ( A [,] B ) ) -> C e. RR )
24 23 adantrr
 |-  ( ( ph /\ ( C e. ( A [,] B ) /\ C =/= A ) ) -> C e. RR )
25 8 adantr
 |-  ( ( ph /\ C e. ( A [,] B ) ) -> A e. RR* )
26 18 adantr
 |-  ( ( ph /\ C e. ( A [,] B ) ) -> B e. RR* )
27 simpr
 |-  ( ( ph /\ C e. ( A [,] B ) ) -> C e. ( A [,] B ) )
28 iccgelb
 |-  ( ( A e. RR* /\ B e. RR* /\ C e. ( A [,] B ) ) -> A <_ C )
29 25 26 27 28 syl3anc
 |-  ( ( ph /\ C e. ( A [,] B ) ) -> A <_ C )
30 29 adantrr
 |-  ( ( ph /\ ( C e. ( A [,] B ) /\ C =/= A ) ) -> A <_ C )
31 simprr
 |-  ( ( ph /\ ( C e. ( A [,] B ) /\ C =/= A ) ) -> C =/= A )
32 21 24 30 31 leneltd
 |-  ( ( ph /\ ( C e. ( A [,] B ) /\ C =/= A ) ) -> A < C )
33 iccleub
 |-  ( ( A e. RR* /\ B e. RR* /\ C e. ( A [,] B ) ) -> C <_ B )
34 25 26 27 33 syl3anc
 |-  ( ( ph /\ C e. ( A [,] B ) ) -> C <_ B )
35 34 adantrr
 |-  ( ( ph /\ ( C e. ( A [,] B ) /\ C =/= A ) ) -> C <_ B )
36 17 19 20 32 35 eliocd
 |-  ( ( ph /\ ( C e. ( A [,] B ) /\ C =/= A ) ) -> C e. ( A (,] B ) )
37 16 36 impbida
 |-  ( ph -> ( C e. ( A (,] B ) <-> ( C e. ( A [,] B ) /\ C =/= A ) ) )