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Metamath Proof Explorer


Theorem 19.39

Description: Theorem 19.39 of Margaris p. 90. (Contributed by NM, 12-Mar-1993)

Ref Expression
Assertion 19.39 x φ x ψ x φ ψ

Proof

Step Hyp Ref Expression
1 19.2 x φ x φ
2 1 imim1i x φ x ψ x φ x ψ
3 19.35 x φ ψ x φ x ψ
4 2 3 sylibr x φ x ψ x φ ψ