Metamath Proof Explorer


Theorem pmodN

Description: The modular law for projective subspaces. (Contributed by NM, 26-Mar-2012) (New usage is discouraged.)

Ref Expression
Hypotheses pmod.a A=AtomsK
pmod.s S=PSubSpK
pmod.p +˙=+𝑃K
Assertion pmodN KHLXSYAZAXY+˙XZ=XY+˙XZ

Proof

Step Hyp Ref Expression
1 pmod.a A=AtomsK
2 pmod.s S=PSubSpK
3 pmod.p +˙=+𝑃K
4 incom XXZ+˙Y=XZ+˙YX
5 hllat KHLKLat
6 5 adantr KHLXSYAZAKLat
7 simpr2 KHLXSYAZAYA
8 inss2 XZZ
9 simpr3 KHLXSYAZAZA
10 8 9 sstrid KHLXSYAZAXZA
11 1 3 paddcom KLatYAXZAY+˙XZ=XZ+˙Y
12 6 7 10 11 syl3anc KHLXSYAZAY+˙XZ=XZ+˙Y
13 12 ineq2d KHLXSYAZAXY+˙XZ=XXZ+˙Y
14 incom XY=YX
15 14 oveq2i XZ+˙XY=XZ+˙YX
16 inss2 XYY
17 16 7 sstrid KHLXSYAZAXYA
18 1 3 paddcom KLatXYAXZAXY+˙XZ=XZ+˙XY
19 6 17 10 18 syl3anc KHLXSYAZAXY+˙XZ=XZ+˙XY
20 simpr1 KHLXSYAZAXS
21 10 7 20 3jca KHLXSYAZAXZAYAXS
22 inss1 XZX
23 1 2 3 pmod1i KHLXZAYAXSXZXXZ+˙YX=XZ+˙YX
24 22 23 mpi KHLXZAYAXSXZ+˙YX=XZ+˙YX
25 21 24 syldan KHLXSYAZAXZ+˙YX=XZ+˙YX
26 15 19 25 3eqtr4a KHLXSYAZAXY+˙XZ=XZ+˙YX
27 4 13 26 3eqtr4a KHLXSYAZAXY+˙XZ=XY+˙XZ