Metamath Proof Explorer


Theorem bj-iminvid

Description: Functorial property of the inverse image: the inverse image by the identity on a set is the identity on the powerset. (Contributed by BJ, 26-May-2024)

Ref Expression
Hypothesis bj-iminvid.ex φAU
Assertion bj-iminvid Could not format assertion : No typesetting found for |- ( ph -> ( ( A ~P^* A ) ` ( _I |` A ) ) = ( _I |` ~P A ) ) with typecode |-

Proof

Step Hyp Ref Expression
1 bj-iminvid.ex φAU
2 idssxp IAA×A
3 2 a1i φIAA×A
4 1 1 3 bj-iminvval2 Could not format ( ph -> ( ( A ~P^* A ) ` ( _I |` A ) ) = { <. x , y >. | ( ( x C_ A /\ y C_ A ) /\ x = ( `' ( _I |` A ) " y ) ) } ) : No typesetting found for |- ( ph -> ( ( A ~P^* A ) ` ( _I |` A ) ) = { <. x , y >. | ( ( x C_ A /\ y C_ A ) /\ x = ( `' ( _I |` A ) " y ) ) } ) with typecode |-
5 cnvresid IA-1=IA
6 5 imaeq1i IA-1y=IAy
7 resiima yAIAy=y
8 6 7 eqtrid yAIA-1y=y
9 8 adantl xAyAIA-1y=y
10 9 eqeq2d xAyAx=IA-1yx=y
11 10 bj-imdiridlem xy|xAyAx=IA-1y=I𝒫A
12 4 11 eqtrdi Could not format ( ph -> ( ( A ~P^* A ) ` ( _I |` A ) ) = ( _I |` ~P A ) ) : No typesetting found for |- ( ph -> ( ( A ~P^* A ) ` ( _I |` A ) ) = ( _I |` ~P A ) ) with typecode |-