Metamath Proof Explorer


Theorem iocinioc2

Description: Intersection between two open-below, closed-above intervals sharing the same upper bound. (Contributed by Thierry Arnoux, 7-Aug-2017)

Ref Expression
Assertion iocinioc2 A*B*C*ABACBC=BC

Proof

Step Hyp Ref Expression
1 elin xACBCxACxBC
2 simpl1 A*B*C*ABA*
3 simpl3 A*B*C*ABC*
4 elioc1 A*C*xACx*A<xxC
5 2 3 4 syl2anc A*B*C*ABxACx*A<xxC
6 simpl2 A*B*C*ABB*
7 elioc1 B*C*xBCx*B<xxC
8 6 3 7 syl2anc A*B*C*ABxBCx*B<xxC
9 5 8 anbi12d A*B*C*ABxACxBCx*A<xxCx*B<xxC
10 simp31 A*B*C*ABx*B<xxCx*
11 2 3adant3 A*B*C*ABx*B<xxCA*
12 6 3adant3 A*B*C*ABx*B<xxCB*
13 simp2 A*B*C*ABx*B<xxCAB
14 simp32 A*B*C*ABx*B<xxCB<x
15 11 12 10 13 14 xrlelttrd A*B*C*ABx*B<xxCA<x
16 simp33 A*B*C*ABx*B<xxCxC
17 10 15 16 3jca A*B*C*ABx*B<xxCx*A<xxC
18 17 3expia A*B*C*ABx*B<xxCx*A<xxC
19 18 pm4.71rd A*B*C*ABx*B<xxCx*A<xxCx*B<xxC
20 9 19 bitr4d A*B*C*ABxACxBCx*B<xxC
21 1 20 bitrid A*B*C*ABxACBCx*B<xxC
22 21 8 bitr4d A*B*C*ABxACBCxBC
23 22 eqrdv A*B*C*ABACBC=BC