Theorem mgmb1mgm1 13531

Description: The only magma with a base set consisting of one element is the trivial magma (at least if its operation is an internal binary operation). (Contributed by AV, 23-Jan-2020.) (Revised by AV, 7-Feb-2020.)

Hypotheses

Ref	Expression
mgmb1mgm1.b	|- B = ( Base ` M )
mgmb1mgm1.p	|- .+ = ( +g ` M )

Assertion

Ref	Expression
mgmb1mgm1	|- ( ( M e. Mgm /\ Z e. B /\ .+ Fn ( B X. B ) ) -> ( B = { Z } <-> .+ = { <. <. Z , Z >. , Z >. } ) )

Proof of Theorem mgmb1mgm1

Step	Hyp	Ref	Expression
1		mgmb1mgm1.b	. . . . . 6 |- B = ( Base ` M )
2		eqid 2231	. . . . . 6 |- ( +f ` M ) = ( +f ` M )
3	1, 2	mgmplusf 13529	. . . . 5 |- ( M e. Mgm -> ( +f ` M ) : ( B X. B ) --> B )
4	3	adantr 276	. . . 4 |- ( ( M e. Mgm /\ .+ Fn ( B X. B ) ) -> ( +f ` M ) : ( B X. B ) --> B )
5		mgmb1mgm1.p	. . . . . 6 |- .+ = ( +g ` M )
6	1, 5, 2	plusfeqg 13527	. . . . 5 |- ( ( M e. Mgm /\ .+ Fn ( B X. B ) ) -> ( +f ` M ) = .+ )
7	6	feq1d 5476	. . . 4 |- ( ( M e. Mgm /\ .+ Fn ( B X. B ) ) -> ( ( +f ` M ) : ( B X. B ) --> B <-> .+ : ( B X. B ) --> B ) )
8	4, 7	mpbid 147	. . 3 |- ( ( M e. Mgm /\ .+ Fn ( B X. B ) ) -> .+ : ( B X. B ) --> B )
9	8	3adant2 1043	. 2 |- ( ( M e. Mgm /\ Z e. B /\ .+ Fn ( B X. B ) ) -> .+ : ( B X. B ) --> B )
10		simp2 1025	. 2 |- ( ( M e. Mgm /\ Z e. B /\ .+ Fn ( B X. B ) ) -> Z e. B )
11		intopsn 13530	. 2 |- ( ( .+ : ( B X. B ) --> B /\ Z e. B ) -> ( B = { Z } <-> .+ = { <. <. Z , Z >. , Z >. } ) )
12	9, 10, 11	syl2anc 411	1 |- ( ( M e. Mgm /\ Z e. B /\ .+ Fn ( B X. B ) ) -> ( B = { Z } <-> .+ = { <. <. Z , Z >. , Z >. } ) )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   /\ w3a 1005   = wceq 1398   e. wcel 2202   {csn 3673   <.cop 3676   X. cxp 4729   Fn wfn 5328   -->wf 5329   ` cfv 5333   Basecbs 13162   +g cplusg 13240   +fcplusf 13516  Mgmcmgm 13517

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-13 2204  ax-14 2205  ax-ext 2213  ax-coll 4209  ax-sep 4212  ax-pow 4270  ax-pr 4305  ax-un 4536  ax-cnex 8183  ax-resscn 8184  ax-1re 8186  ax-addrcl 8189

This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-nf 1510  df-sb 1811  df-eu 2082  df-mo 2083  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2364  df-ral 2516  df-rex 2517  df-reu 2518  df-rab 2520  df-v 2805  df-sbc 3033  df-csb 3129  df-un 3205  df-in 3207  df-ss 3214  df-pw 3658  df-sn 3679  df-pr 3680  df-op 3682  df-uni 3899  df-int 3934  df-iun 3977  df-br 4094  df-opab 4156  df-mpt 4157  df-id 4396  df-xp 4737  df-rel 4738  df-cnv 4739  df-co 4740  df-dm 4741  df-rn 4742  df-res 4743  df-ima 4744  df-iota 5293  df-fun 5335  df-fn 5336  df-f 5337  df-f1 5338  df-fo 5339  df-f1o 5340  df-fv 5341  df-ov 6031  df-oprab 6032  df-mpo 6033  df-1st 6312  df-2nd 6313  df-inn 9203  df-2 9261  df-ndx 13165  df-slot 13166  df-base 13168  df-plusg 13253  df-plusf 13518  df-mgm 13519

This theorem is referenced by:  srg1zr  14081