Metamath Proof Explorer


Theorem abanssl

Description: A class abstraction with a conjunction is a subset of the class abstraction with the left conjunct only. (Contributed by AV, 7-Aug-2024) (Proof shortened by SN, 22-Aug-2024)

Ref Expression
Assertion abanssl
|- { f | ( ph /\ ps ) } C_ { f | ph }

Proof

Step Hyp Ref Expression
1 simpl
 |-  ( ( ph /\ ps ) -> ph )
2 1 ss2abi
 |-  { f | ( ph /\ ps ) } C_ { f | ph }