Theorem 3anbi23d

Deduction conjoining and adding a conjunct to equivalences. (Contributed by NM, 8-Sep-2006.)

Hypotheses
3anbi12d.1
\( \vdash \varphi \rightarrow (\psi \leftrightarrow \chi) \)
3anbi12d.2
\( \vdash \varphi \rightarrow (\theta \leftrightarrow \tau) \)
Conclusion
\( \vdash \varphi \rightarrow (\eta \wedge \psi \wedge \theta \leftrightarrow \eta \wedge \chi \wedge \tau) \)
Proof
l0
biidd
l1
3anbi12d.1
3anbi12d.2
3anbi123d l0 l1 _