Theorem exlimdvv

Deduction form of Theorem 19.23 of [Margaris] p. 90, see 19.23. (Contributed by NM, 31-Jul-1995.)

Hypothesis
exlimdvv.1
\( \vdash \varphi \rightarrow \psi \rightarrow \chi \)
Conclusion
\( \vdash \varphi \rightarrow \exists x \, \exists y \, \psi \rightarrow \chi \)
Proof
exlimdvv.1
exlimdv _
exlimdv _