Metamath Proof Explorer


Theorem csmdsymi

Description: Cross-symmetry implies M-symmetry. Theorem 1.9.1 of MaedaMaeda p. 3. (Contributed by NM, 24-Dec-2006) (New usage is discouraged.)

Ref Expression
Hypotheses csmdsym.1 AC
csmdsym.2 BC
Assertion csmdsymi cCc𝑀BB𝑀*cA𝑀BB𝑀A

Proof

Step Hyp Ref Expression
1 csmdsym.1 AC
2 csmdsym.2 BC
3 incom AB=BA
4 3 sseq1i ABxBAx
5 4 biimpri BAxABx
6 chjcom xCBCxB=Bx
7 2 6 mpan2 xCxB=Bx
8 7 ineq1d xCxBA=BxA
9 incom BxA=ABx
10 8 9 eqtrdi xCxBA=ABx
11 10 ad2antlr cCc𝑀BB𝑀*cA𝑀BxCABxxAxBA=ABx
12 2 a1i xCBC
13 id xCxC
14 1 a1i xCAC
15 12 13 14 3jca xCBCxCAC
16 15 ad2antlr cCc𝑀BB𝑀*cA𝑀BxCABxxABCxCAC
17 inss2 ABB
18 ssid BB
19 17 18 pm3.2i ABBBB
20 sseq2 x=ifxCx0ABxABifxCx0
21 sseq1 x=ifxCx0xAifxCx0A
22 20 21 anbi12d x=ifxCx0ABxxAABifxCx0ifxCx0A
23 22 3anbi2d x=ifxCx0A𝑀BABxxAABBBBA𝑀BABifxCx0ifxCx0AABBBB
24 breq1 x=ifxCx0x𝑀BifxCx0𝑀B
25 23 24 imbi12d x=ifxCx0A𝑀BABxxAABBBBx𝑀BA𝑀BABifxCx0ifxCx0AABBBBifxCx0𝑀B
26 h0elch 0C
27 26 elimel ifxCx0C
28 1 2 27 2 mdslmd4i A𝑀BABifxCx0ifxCx0AABBBBifxCx0𝑀B
29 25 28 dedth xCA𝑀BABxxAABBBBx𝑀B
30 29 com12 A𝑀BABxxAABBBBxCx𝑀B
31 19 30 mp3an3 A𝑀BABxxAxCx𝑀B
32 31 imp A𝑀BABxxAxCx𝑀B
33 32 an32s A𝑀BxCABxxAx𝑀B
34 33 adantlll cCc𝑀BB𝑀*cA𝑀BxCABxxAx𝑀B
35 breq1 c=xc𝑀Bx𝑀B
36 breq2 c=xB𝑀*cB𝑀*x
37 35 36 imbi12d c=xc𝑀BB𝑀*cx𝑀BB𝑀*x
38 37 rspccva cCc𝑀BB𝑀*cxCx𝑀BB𝑀*x
39 38 adantlr cCc𝑀BB𝑀*cA𝑀BxCx𝑀BB𝑀*x
40 39 adantr cCc𝑀BB𝑀*cA𝑀BxCABxxAx𝑀BB𝑀*x
41 34 40 mpd cCc𝑀BB𝑀*cA𝑀BxCABxxAB𝑀*x
42 simprr cCc𝑀BB𝑀*cA𝑀BxCABxxAxA
43 dmdi BCxCACB𝑀*xxAABx=ABx
44 16 41 42 43 syl12anc cCc𝑀BB𝑀*cA𝑀BxCABxxAABx=ABx
45 1 2 chincli ABC
46 chjcom ABCxCABx=xAB
47 45 46 mpan xCABx=xAB
48 3 oveq2i xAB=xBA
49 47 48 eqtrdi xCABx=xBA
50 49 ad2antlr cCc𝑀BB𝑀*cA𝑀BxCABxxAABx=xBA
51 11 44 50 3eqtr2d cCc𝑀BB𝑀*cA𝑀BxCABxxAxBA=xBA
52 51 ex cCc𝑀BB𝑀*cA𝑀BxCABxxAxBA=xBA
53 5 52 sylani cCc𝑀BB𝑀*cA𝑀BxCBAxxAxBA=xBA
54 53 ralrimiva cCc𝑀BB𝑀*cA𝑀BxCBAxxAxBA=xBA
55 2 1 mdsl2bi B𝑀AxCBAxxAxBA=xBA
56 54 55 sylibr cCc𝑀BB𝑀*cA𝑀BB𝑀A