Database
CLASSICAL FIRST-ORDER LOGIC WITH EQUALITY
Propositional calculus
Abbreviated conjunction and disjunction of three wff's
mp3an3an
Metamath Proof Explorer
Description: mp3an with antecedents in standard conjunction form and with two
hypotheses which are implications. (Contributed by Alan Sare , 28-Aug-2016)
Ref
Expression
Hypotheses
mp3an3an.1
⊢ φ
mp3an3an.2
⊢ ψ → χ
mp3an3an.3
⊢ θ → τ
mp3an3an.4
⊢ φ ∧ χ ∧ τ → η
Assertion
mp3an3an
⊢ ψ ∧ θ → η
Proof
Step
Hyp
Ref
Expression
1
mp3an3an.1
⊢ φ
2
mp3an3an.2
⊢ ψ → χ
3
mp3an3an.3
⊢ θ → τ
4
mp3an3an.4
⊢ φ ∧ χ ∧ τ → η
5
1 4
mp3an1
⊢ χ ∧ τ → η
6
2 3 5
syl2an
⊢ ψ ∧ θ → η