Metamath Proof Explorer


Theorem irredn0

Description: The additive identity is not irreducible. (Contributed by Mario Carneiro, 4-Dec-2014)

Ref Expression
Hypotheses irredn0.i
|- I = ( Irred ` R )
irredn0.z
|- .0. = ( 0g ` R )
Assertion irredn0
|- ( ( R e. Ring /\ X e. I ) -> X =/= .0. )

Proof

Step Hyp Ref Expression
1 irredn0.i
 |-  I = ( Irred ` R )
2 irredn0.z
 |-  .0. = ( 0g ` R )
3 eqid
 |-  ( Base ` R ) = ( Base ` R )
4 3 2 ring0cl
 |-  ( R e. Ring -> .0. e. ( Base ` R ) )
5 4 anim1i
 |-  ( ( R e. Ring /\ -. .0. e. ( Unit ` R ) ) -> ( .0. e. ( Base ` R ) /\ -. .0. e. ( Unit ` R ) ) )
6 eldif
 |-  ( .0. e. ( ( Base ` R ) \ ( Unit ` R ) ) <-> ( .0. e. ( Base ` R ) /\ -. .0. e. ( Unit ` R ) ) )
7 5 6 sylibr
 |-  ( ( R e. Ring /\ -. .0. e. ( Unit ` R ) ) -> .0. e. ( ( Base ` R ) \ ( Unit ` R ) ) )
8 eqid
 |-  ( .r ` R ) = ( .r ` R )
9 3 8 2 ringlz
 |-  ( ( R e. Ring /\ .0. e. ( Base ` R ) ) -> ( .0. ( .r ` R ) .0. ) = .0. )
10 4 9 mpdan
 |-  ( R e. Ring -> ( .0. ( .r ` R ) .0. ) = .0. )
11 10 adantr
 |-  ( ( R e. Ring /\ -. .0. e. ( Unit ` R ) ) -> ( .0. ( .r ` R ) .0. ) = .0. )
12 oveq1
 |-  ( x = .0. -> ( x ( .r ` R ) y ) = ( .0. ( .r ` R ) y ) )
13 12 eqeq1d
 |-  ( x = .0. -> ( ( x ( .r ` R ) y ) = .0. <-> ( .0. ( .r ` R ) y ) = .0. ) )
14 oveq2
 |-  ( y = .0. -> ( .0. ( .r ` R ) y ) = ( .0. ( .r ` R ) .0. ) )
15 14 eqeq1d
 |-  ( y = .0. -> ( ( .0. ( .r ` R ) y ) = .0. <-> ( .0. ( .r ` R ) .0. ) = .0. ) )
16 13 15 rspc2ev
 |-  ( ( .0. e. ( ( Base ` R ) \ ( Unit ` R ) ) /\ .0. e. ( ( Base ` R ) \ ( Unit ` R ) ) /\ ( .0. ( .r ` R ) .0. ) = .0. ) -> E. x e. ( ( Base ` R ) \ ( Unit ` R ) ) E. y e. ( ( Base ` R ) \ ( Unit ` R ) ) ( x ( .r ` R ) y ) = .0. )
17 7 7 11 16 syl3anc
 |-  ( ( R e. Ring /\ -. .0. e. ( Unit ` R ) ) -> E. x e. ( ( Base ` R ) \ ( Unit ` R ) ) E. y e. ( ( Base ` R ) \ ( Unit ` R ) ) ( x ( .r ` R ) y ) = .0. )
18 17 ex
 |-  ( R e. Ring -> ( -. .0. e. ( Unit ` R ) -> E. x e. ( ( Base ` R ) \ ( Unit ` R ) ) E. y e. ( ( Base ` R ) \ ( Unit ` R ) ) ( x ( .r ` R ) y ) = .0. ) )
19 18 orrd
 |-  ( R e. Ring -> ( .0. e. ( Unit ` R ) \/ E. x e. ( ( Base ` R ) \ ( Unit ` R ) ) E. y e. ( ( Base ` R ) \ ( Unit ` R ) ) ( x ( .r ` R ) y ) = .0. ) )
20 eqid
 |-  ( Unit ` R ) = ( Unit ` R )
21 eqid
 |-  ( ( Base ` R ) \ ( Unit ` R ) ) = ( ( Base ` R ) \ ( Unit ` R ) )
22 3 20 1 21 8 isnirred
 |-  ( .0. e. ( Base ` R ) -> ( -. .0. e. I <-> ( .0. e. ( Unit ` R ) \/ E. x e. ( ( Base ` R ) \ ( Unit ` R ) ) E. y e. ( ( Base ` R ) \ ( Unit ` R ) ) ( x ( .r ` R ) y ) = .0. ) ) )
23 4 22 syl
 |-  ( R e. Ring -> ( -. .0. e. I <-> ( .0. e. ( Unit ` R ) \/ E. x e. ( ( Base ` R ) \ ( Unit ` R ) ) E. y e. ( ( Base ` R ) \ ( Unit ` R ) ) ( x ( .r ` R ) y ) = .0. ) ) )
24 19 23 mpbird
 |-  ( R e. Ring -> -. .0. e. I )
25 24 adantr
 |-  ( ( R e. Ring /\ X e. I ) -> -. .0. e. I )
26 simpr
 |-  ( ( R e. Ring /\ X e. I ) -> X e. I )
27 eleq1
 |-  ( X = .0. -> ( X e. I <-> .0. e. I ) )
28 26 27 syl5ibcom
 |-  ( ( R e. Ring /\ X e. I ) -> ( X = .0. -> .0. e. I ) )
29 28 necon3bd
 |-  ( ( R e. Ring /\ X e. I ) -> ( -. .0. e. I -> X =/= .0. ) )
30 25 29 mpd
 |-  ( ( R e. Ring /\ X e. I ) -> X =/= .0. )