Metamath Proof Explorer


Theorem imbi12d2a

Description: Variant of imbi12d2 . (Contributed by Zhi Wang, 30-Aug-2024)

Ref Expression
Hypotheses imbi12d2.1 φ ψ χ
imbi12d2a.2 φ ψ θ τ
Assertion imbi12d2a φ ψ θ χ τ

Proof

Step Hyp Ref Expression
1 imbi12d2.1 φ ψ χ
2 imbi12d2a.2 φ ψ θ τ
3 2 ex φ ψ θ τ
4 1 3 imbi12d2 φ ψ θ χ τ