Metamath Proof Explorer


Theorem ifexd

Description: Existence of the conditional operator (deduction form). (Contributed by SN, 26-Jul-2024)

Ref Expression
Hypotheses ifexd.1 ⊢ ( 𝜑 → 𝐴 ∈ 𝑉 )
ifexd.2 ⊢ ( 𝜑 → 𝐵 ∈ 𝑊 )
Assertion ifexd ( 𝜑 → if ( 𝜓 , 𝐴 , 𝐵 ) ∈ V )

Proof

Step Hyp Ref Expression
1 ifexd.1 ⊢ ( 𝜑 → 𝐴 ∈ 𝑉 )
2 ifexd.2 ⊢ ( 𝜑 → 𝐵 ∈ 𝑊 )
3 1 elexd ⊢ ( 𝜑 → 𝐴 ∈ V )
4 2 elexd ⊢ ( 𝜑 → 𝐵 ∈ V )
5 3 4 ifcld ⊢ ( 𝜑 → if ( 𝜓 , 𝐴 , 𝐵 ) ∈ V )