Metamath Proof Explorer


Theorem iooshf

Description: Shift the arguments of the open interval function. (Contributed by NM, 17-Aug-2008)

Ref Expression
Assertion iooshf ABCDABCDAC+BD+B

Proof

Step Hyp Ref Expression
1 ltaddsub CBAC+B<AC<AB
2 1 3com13 ABCC+B<AC<AB
3 2 3expa ABCC+B<AC<AB
4 3 adantrr ABCDC+B<AC<AB
5 ltsubadd ABDAB<DA<D+B
6 5 bicomd ABDA<D+BAB<D
7 6 3expa ABDA<D+BAB<D
8 7 adantrl ABCDA<D+BAB<D
9 4 8 anbi12d ABCDC+B<AA<D+BC<ABAB<D
10 readdcl CBC+B
11 10 rexrd CBC+B*
12 11 ad2ant2rl CDABC+B*
13 readdcl DBD+B
14 13 rexrd DBD+B*
15 14 ad2ant2l CDABD+B*
16 rexr AA*
17 16 ad2antrl CDABA*
18 elioo5 C+B*D+B*A*AC+BD+BC+B<AA<D+B
19 12 15 17 18 syl3anc CDABAC+BD+BC+B<AA<D+B
20 19 ancoms ABCDAC+BD+BC+B<AA<D+B
21 rexr CC*
22 21 ad2antrl ABCDC*
23 rexr DD*
24 23 ad2antll ABCDD*
25 resubcl ABAB
26 25 rexrd ABAB*
27 26 adantr ABCDAB*
28 elioo5 C*D*AB*ABCDC<ABAB<D
29 22 24 27 28 syl3anc ABCDABCDC<ABAB<D
30 9 20 29 3bitr4rd ABCDABCDAC+BD+B