Metamath Proof Explorer


Theorem ntrclsrcomplex

Description: The relative complement of the class S exists as a subset of the base set. (Contributed by RP, 25-Jun-2021)

Ref Expression
Hypotheses ntrclsbex.d 𝐷 = ( 𝑂𝐵 )
ntrclsbex.r ( 𝜑𝐼 𝐷 𝐾 )
Assertion ntrclsrcomplex ( 𝜑 → ( 𝐵𝑆 ) ∈ 𝒫 𝐵 )

Proof

Step Hyp Ref Expression
1 ntrclsbex.d 𝐷 = ( 𝑂𝐵 )
2 ntrclsbex.r ( 𝜑𝐼 𝐷 𝐾 )
3 1 2 ntrclsbex ( 𝜑𝐵 ∈ V )
4 difssd ( 𝜑 → ( 𝐵𝑆 ) ⊆ 𝐵 )
5 3 4 sselpwd ( 𝜑 → ( 𝐵𝑆 ) ∈ 𝒫 𝐵 )