Metamath Proof Explorer


Theorem anbi2ci

Description: Variant of anbi2i with commutation. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (Proof shortened by Andrew Salmon, 14-Jun-2011)

Ref Expression
Hypothesis anbi.1 ⊢ φ ↔ ψ
Assertion anbi2ci ⊢ φ ∧ χ ↔ χ ∧ ψ

Proof

Step Hyp Ref Expression
1 anbi.1 ⊢ φ ↔ ψ
2 1 anbi1i ⊢ φ ∧ χ ↔ ψ ∧ χ
3 2 biancomi ⊢ φ ∧ χ ↔ χ ∧ ψ