Step |
Hyp |
Ref |
Expression |
1 |
|
pidlnzb.1 |
|- B = ( Base ` R ) |
2 |
|
pidlnzb.2 |
|- .0. = ( 0g ` R ) |
3 |
|
pidlnzb.3 |
|- K = ( RSpan ` R ) |
4 |
1 2 3
|
pidlnz |
|- ( ( R e. Ring /\ X e. B /\ X =/= .0. ) -> ( K ` { X } ) =/= { .0. } ) |
5 |
4
|
3expa |
|- ( ( ( R e. Ring /\ X e. B ) /\ X =/= .0. ) -> ( K ` { X } ) =/= { .0. } ) |
6 |
|
sneq |
|- ( X = .0. -> { X } = { .0. } ) |
7 |
6
|
fveq2d |
|- ( X = .0. -> ( K ` { X } ) = ( K ` { .0. } ) ) |
8 |
7
|
adantl |
|- ( ( ( R e. Ring /\ X e. B ) /\ X = .0. ) -> ( K ` { X } ) = ( K ` { .0. } ) ) |
9 |
3 2
|
rsp0 |
|- ( R e. Ring -> ( K ` { .0. } ) = { .0. } ) |
10 |
9
|
ad2antrr |
|- ( ( ( R e. Ring /\ X e. B ) /\ X = .0. ) -> ( K ` { .0. } ) = { .0. } ) |
11 |
8 10
|
eqtrd |
|- ( ( ( R e. Ring /\ X e. B ) /\ X = .0. ) -> ( K ` { X } ) = { .0. } ) |
12 |
11
|
ex |
|- ( ( R e. Ring /\ X e. B ) -> ( X = .0. -> ( K ` { X } ) = { .0. } ) ) |
13 |
12
|
necon3d |
|- ( ( R e. Ring /\ X e. B ) -> ( ( K ` { X } ) =/= { .0. } -> X =/= .0. ) ) |
14 |
13
|
imp |
|- ( ( ( R e. Ring /\ X e. B ) /\ ( K ` { X } ) =/= { .0. } ) -> X =/= .0. ) |
15 |
5 14
|
impbida |
|- ( ( R e. Ring /\ X e. B ) -> ( X =/= .0. <-> ( K ` { X } ) =/= { .0. } ) ) |