Metamath Proof Explorer


Theorem fh4i

Description: Variation of the Foulis-Holland Theorem. (Contributed by NM, 16-Jan-2005) (New usage is discouraged.)

Ref Expression
Hypotheses fh1.1 A C
fh1.2 B C
fh1.3 C C
fh1.4 A 𝐶 B
fh1.5 A 𝐶 C
Assertion fh4i B A C = B A B C

Proof

Step Hyp Ref Expression
1 fh1.1 A C
2 fh1.2 B C
3 fh1.3 C C
4 fh1.4 A 𝐶 B
5 fh1.5 A 𝐶 C
6 1 choccli A C
7 2 choccli B C
8 3 choccli C C
9 1 2 4 cmcm3ii A 𝐶 B
10 6 2 9 cmcm2ii A 𝐶 B
11 1 3 5 cmcm3ii A 𝐶 C
12 6 3 11 cmcm2ii A 𝐶 C
13 6 7 8 10 12 fh2i B A C = B A B C
14 1 3 chdmm1i A C = A C
15 14 ineq2i B A C = B A C
16 2 1 chdmj1i B A = B A
17 2 3 chdmj1i B C = B C
18 16 17 oveq12i B A B C = B A B C
19 13 15 18 3eqtr4ri B A B C = B A C
20 2 1 chjcli B A C
21 2 3 chjcli B C C
22 20 21 chdmm1i B A B C = B A B C
23 1 3 chincli A C C
24 2 23 chdmj1i B A C = B A C
25 19 22 24 3eqtr4i B A B C = B A C
26 2 23 chjcli B A C C
27 20 21 chincli B A B C C
28 26 27 chcon3i B A C = B A B C B A B C = B A C
29 25 28 mpbir B A C = B A B C