Metamath Proof Explorer


Theorem fzmaxdif

Description: Bound on the difference between two integers constrained to two possibly overlapping finite ranges. (Contributed by Stefan O'Rear, 4-Oct-2014)

Ref Expression
Assertion fzmaxdif CABCFDEFCEFBADFB

Proof

Step Hyp Ref Expression
1 simp2r CABCFDEFCEFBDEF
2 1 elfzelzd CABCFDEFCEFBD
3 2 zred CABCFDEFCEFBD
4 simp2l CABCFDEFCEFBF
5 4 zred CABCFDEFCEFBF
6 simp1r CABCFDEFCEFBABC
7 elfzel1 ABCB
8 6 7 syl CABCFDEFCEFBB
9 8 zred CABCFDEFCEFBB
10 5 9 resubcld CABCFDEFCEFBFB
11 3 10 resubcld CABCFDEFCEFBDFB
12 6 elfzelzd CABCFDEFCEFBA
13 12 zred CABCFDEFCEFBA
14 elfzle2 DEFDF
15 1 14 syl CABCFDEFCEFBDF
16 3 5 10 15 lesub1dd CABCFDEFCEFBDFBFFB
17 5 recnd CABCFDEFCEFBF
18 9 recnd CABCFDEFCEFBB
19 17 18 nncand CABCFDEFCEFBFFB=B
20 16 19 breqtrd CABCFDEFCEFBDFBB
21 elfzle1 ABCBA
22 6 21 syl CABCFDEFCEFBBA
23 11 9 13 20 22 letrd CABCFDEFCEFBDFBA
24 simp1l CABCFDEFCEFBC
25 24 zred CABCFDEFCEFBC
26 3 10 readdcld CABCFDEFCEFBD+F-B
27 elfzle2 ABCAC
28 6 27 syl CABCFDEFCEFBAC
29 25 3 resubcld CABCFDEFCEFBCD
30 elfzel1 DEFE
31 1 30 syl CABCFDEFCEFBE
32 31 zred CABCFDEFCEFBE
33 25 32 resubcld CABCFDEFCEFBCE
34 elfzle1 DEFED
35 1 34 syl CABCFDEFCEFBED
36 32 3 25 35 lesub2dd CABCFDEFCEFBCDCE
37 simp3 CABCFDEFCEFBCEFB
38 29 33 10 36 37 letrd CABCFDEFCEFBCDFB
39 25 3 10 lesubaddd CABCFDEFCEFBCDFBCF-B+D
40 38 39 mpbid CABCFDEFCEFBCF-B+D
41 10 recnd CABCFDEFCEFBFB
42 3 recnd CABCFDEFCEFBD
43 41 42 addcomd CABCFDEFCEFBF-B+D=D+F-B
44 40 43 breqtrd CABCFDEFCEFBCD+F-B
45 13 25 26 28 44 letrd CABCFDEFCEFBAD+F-B
46 13 3 10 absdifled CABCFDEFCEFBADFBDFBAAD+F-B
47 23 45 46 mpbir2and CABCFDEFCEFBADFB