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Theorem efald2 32937
Description: A proof by contradiction. (Contributed by Giovanni Mascellani, 15-Sep-2017.)
Hypothesis
Ref Expression
efald2.1 𝜑 → ⊥)
Assertion
Ref Expression
efald2 𝜑

Proof of Theorem efald2
StepHypRef Expression
1 efald2.1 . . . 4 𝜑 → ⊥)
21adantl 480 . . 3 ((⊤ ∧ ¬ 𝜑) → ⊥)
32efald 1494 . 2 (⊤ → 𝜑)
43trud 1483 1 𝜑
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3  wi 4  wtru 1475  wfal 1479
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8
This theorem depends on definitions:  df-bi 195  df-an 384  df-tru 1477  df-fal 1480
This theorem is referenced by:  mpt2bi123f  33031  mptbi12f  33035  ac6s6  33040
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