Metamath Proof Explorer


Theorem exp32

Description: An exportation inference. (Contributed by NM, 26-Apr-1994)

Ref Expression
Hypothesis exp32.1 φψχθ
Assertion exp32 φψχθ

Proof

Step Hyp Ref Expression
1 exp32.1 φψχθ
2 1 ex φψχθ
3 2 expd φψχθ