Database
CLASSICAL FIRST-ORDER LOGIC WITH EQUALITY
Propositional calculus
Logical conjunction
anim2i
Next ⟩
anim12ii
Metamath Proof Explorer
Ascii
Unicode
Theorem
anim2i
Description:
Introduce conjunct to both sides of an implication.
(Contributed by
NM
, 3-Jan-1993)
Ref
Expression
Hypothesis
anim1i.1
⊢
φ
→
ψ
Assertion
anim2i
⊢
χ
∧
φ
→
χ
∧
ψ
Proof
Step
Hyp
Ref
Expression
1
anim1i.1
⊢
φ
→
ψ
2
id
⊢
χ
→
χ
3
2
1
anim12i
⊢
χ
∧
φ
→
χ
∧
ψ