Metamath Proof Explorer


Theorem coexd

Description: The composition of two sets is a set. (Contributed by SN, 7-Feb-2025)

Ref Expression
Hypotheses coexd.1 ( 𝜑𝐴𝑉 )
coexd.2 ( 𝜑𝐵𝑊 )
Assertion coexd ( 𝜑 → ( 𝐴𝐵 ) ∈ V )

Proof

Step Hyp Ref Expression
1 coexd.1 ( 𝜑𝐴𝑉 )
2 coexd.2 ( 𝜑𝐵𝑊 )
3 coexg ( ( 𝐴𝑉𝐵𝑊 ) → ( 𝐴𝐵 ) ∈ V )
4 1 2 3 syl2anc ( 𝜑 → ( 𝐴𝐵 ) ∈ V )