Metamath Proof Explorer


Theorem adantlll

Description: Deduction adding a conjunct to antecedent. (Contributed by NM, 26-Dec-2004) (Proof shortened by Wolf Lammen, 2-Dec-2012)

Ref Expression
Hypothesis adantl2.1 φψχθ
Assertion adantlll τφψχθ

Proof

Step Hyp Ref Expression
1 adantl2.1 φψχθ
2 simpr τφφ
3 2 1 sylanl1 τφψχθ