Metamath Proof Explorer


Theorem zlmlem

Description: Lemma for zlmbas and zlmplusg . (Contributed by Mario Carneiro, 2-Oct-2015)

Ref Expression
Hypotheses zlmbas.w
|- W = ( ZMod ` G )
zlmlem.2
|- E = Slot N
zlmlem.3
|- N e. NN
zlmlem.4
|- N < 5
Assertion zlmlem
|- ( E ` G ) = ( E ` W )

Proof

Step Hyp Ref Expression
1 zlmbas.w
 |-  W = ( ZMod ` G )
2 zlmlem.2
 |-  E = Slot N
3 zlmlem.3
 |-  N e. NN
4 zlmlem.4
 |-  N < 5
5 2 3 ndxid
 |-  E = Slot ( E ` ndx )
6 2 3 ndxarg
 |-  ( E ` ndx ) = N
7 3 nnrei
 |-  N e. RR
8 6 7 eqeltri
 |-  ( E ` ndx ) e. RR
9 6 4 eqbrtri
 |-  ( E ` ndx ) < 5
10 8 9 ltneii
 |-  ( E ` ndx ) =/= 5
11 scandx
 |-  ( Scalar ` ndx ) = 5
12 10 11 neeqtrri
 |-  ( E ` ndx ) =/= ( Scalar ` ndx )
13 5 12 setsnid
 |-  ( E ` G ) = ( E ` ( G sSet <. ( Scalar ` ndx ) , ZZring >. ) )
14 5lt6
 |-  5 < 6
15 5re
 |-  5 e. RR
16 6re
 |-  6 e. RR
17 8 15 16 lttri
 |-  ( ( ( E ` ndx ) < 5 /\ 5 < 6 ) -> ( E ` ndx ) < 6 )
18 9 14 17 mp2an
 |-  ( E ` ndx ) < 6
19 8 18 ltneii
 |-  ( E ` ndx ) =/= 6
20 vscandx
 |-  ( .s ` ndx ) = 6
21 19 20 neeqtrri
 |-  ( E ` ndx ) =/= ( .s ` ndx )
22 5 21 setsnid
 |-  ( E ` ( G sSet <. ( Scalar ` ndx ) , ZZring >. ) ) = ( E ` ( ( G sSet <. ( Scalar ` ndx ) , ZZring >. ) sSet <. ( .s ` ndx ) , ( .g ` G ) >. ) )
23 13 22 eqtri
 |-  ( E ` G ) = ( E ` ( ( G sSet <. ( Scalar ` ndx ) , ZZring >. ) sSet <. ( .s ` ndx ) , ( .g ` G ) >. ) )
24 eqid
 |-  ( .g ` G ) = ( .g ` G )
25 1 24 zlmval
 |-  ( G e. _V -> W = ( ( G sSet <. ( Scalar ` ndx ) , ZZring >. ) sSet <. ( .s ` ndx ) , ( .g ` G ) >. ) )
26 25 fveq2d
 |-  ( G e. _V -> ( E ` W ) = ( E ` ( ( G sSet <. ( Scalar ` ndx ) , ZZring >. ) sSet <. ( .s ` ndx ) , ( .g ` G ) >. ) ) )
27 23 26 eqtr4id
 |-  ( G e. _V -> ( E ` G ) = ( E ` W ) )
28 2 str0
 |-  (/) = ( E ` (/) )
29 fvprc
 |-  ( -. G e. _V -> ( E ` G ) = (/) )
30 fvprc
 |-  ( -. G e. _V -> ( ZMod ` G ) = (/) )
31 1 30 syl5eq
 |-  ( -. G e. _V -> W = (/) )
32 31 fveq2d
 |-  ( -. G e. _V -> ( E ` W ) = ( E ` (/) ) )
33 28 29 32 3eqtr4a
 |-  ( -. G e. _V -> ( E ` G ) = ( E ` W ) )
34 27 33 pm2.61i
 |-  ( E ` G ) = ( E ` W )