This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: Special substitution for the centralizer of a singleton. (Contributed by Stefan O'Rear, 5-Sep-2015)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | cntzfval.b | |- B = ( Base ` M ) |
|
| cntzfval.p | |- .+ = ( +g ` M ) |
||
| cntzfval.z | |- Z = ( Cntz ` M ) |
||
| Assertion | cntzsnval | |- ( Y e. B -> ( Z ` { Y } ) = { x e. B | ( x .+ Y ) = ( Y .+ x ) } ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | cntzfval.b | |- B = ( Base ` M ) |
|
| 2 | cntzfval.p | |- .+ = ( +g ` M ) |
|
| 3 | cntzfval.z | |- Z = ( Cntz ` M ) |
|
| 4 | snssi | |- ( Y e. B -> { Y } C_ B ) |
|
| 5 | 1 2 3 | cntzval | |- ( { Y } C_ B -> ( Z ` { Y } ) = { x e. B | A. y e. { Y } ( x .+ y ) = ( y .+ x ) } ) |
| 6 | 4 5 | syl | |- ( Y e. B -> ( Z ` { Y } ) = { x e. B | A. y e. { Y } ( x .+ y ) = ( y .+ x ) } ) |
| 7 | oveq2 | |- ( y = Y -> ( x .+ y ) = ( x .+ Y ) ) |
|
| 8 | oveq1 | |- ( y = Y -> ( y .+ x ) = ( Y .+ x ) ) |
|
| 9 | 7 8 | eqeq12d | |- ( y = Y -> ( ( x .+ y ) = ( y .+ x ) <-> ( x .+ Y ) = ( Y .+ x ) ) ) |
| 10 | 9 | ralsng | |- ( Y e. B -> ( A. y e. { Y } ( x .+ y ) = ( y .+ x ) <-> ( x .+ Y ) = ( Y .+ x ) ) ) |
| 11 | 10 | rabbidv | |- ( Y e. B -> { x e. B | A. y e. { Y } ( x .+ y ) = ( y .+ x ) } = { x e. B | ( x .+ Y ) = ( Y .+ x ) } ) |
| 12 | 6 11 | eqtrd | |- ( Y e. B -> ( Z ` { Y } ) = { x e. B | ( x .+ Y ) = ( Y .+ x ) } ) |