Metamath Proof Explorer


Theorem rngolz

Description: The zero of a unital ring is a left-absorbing element. (Contributed by FL, 31-Aug-2009) (New usage is discouraged.)

Ref Expression
Hypotheses ringlz.1 Z=GIdG
ringlz.2 X=ranG
ringlz.3 G=1stR
ringlz.4 H=2ndR
Assertion rngolz RRingOpsAXZHA=Z

Proof

Step Hyp Ref Expression
1 ringlz.1 Z=GIdG
2 ringlz.2 X=ranG
3 ringlz.3 G=1stR
4 ringlz.4 H=2ndR
5 3 rngogrpo RRingOpsGGrpOp
6 2 1 grpoidcl GGrpOpZX
7 2 1 grpolid GGrpOpZXZGZ=Z
8 5 6 7 syl2anc2 RRingOpsZGZ=Z
9 8 adantr RRingOpsAXZGZ=Z
10 9 oveq1d RRingOpsAXZGZHA=ZHA
11 3 2 1 rngo0cl RRingOpsZX
12 11 adantr RRingOpsAXZX
13 simpr RRingOpsAXAX
14 12 12 13 3jca RRingOpsAXZXZXAX
15 3 4 2 rngodir RRingOpsZXZXAXZGZHA=ZHAGZHA
16 14 15 syldan RRingOpsAXZGZHA=ZHAGZHA
17 5 adantr RRingOpsAXGGrpOp
18 simpl RRingOpsAXRRingOps
19 3 4 2 rngocl RRingOpsZXAXZHAX
20 18 12 13 19 syl3anc RRingOpsAXZHAX
21 2 1 grporid GGrpOpZHAXZHAGZ=ZHA
22 21 eqcomd GGrpOpZHAXZHA=ZHAGZ
23 17 20 22 syl2anc RRingOpsAXZHA=ZHAGZ
24 10 16 23 3eqtr3d RRingOpsAXZHAGZHA=ZHAGZ
25 2 grpolcan GGrpOpZHAXZXZHAXZHAGZHA=ZHAGZZHA=Z
26 17 20 12 20 25 syl13anc RRingOpsAXZHAGZHA=ZHAGZZHA=Z
27 24 26 mpbid RRingOpsAXZHA=Z