Metamath Proof Explorer


Theorem inres2

Description: Two ways of expressing the restriction of an intersection. (Contributed by Peter Mazsa, 5-Jun-2021)

Ref Expression
Assertion inres2
|- ( ( R |` A ) i^i S ) = ( ( R i^i S ) |` A )

Proof

Step Hyp Ref Expression
1 inres
 |-  ( S i^i ( R |` A ) ) = ( ( S i^i R ) |` A )
2 1 ineqcomi
 |-  ( ( R |` A ) i^i S ) = ( ( S i^i R ) |` A )
3 incom
 |-  ( R i^i S ) = ( S i^i R )
4 3 reseq1i
 |-  ( ( R i^i S ) |` A ) = ( ( S i^i R ) |` A )
5 2 4 eqtr4i
 |-  ( ( R |` A ) i^i S ) = ( ( R i^i S ) |` A )