><bitr

Theorem.

Arguments:

phi (pr), psi (pr), chi (pr),

Hypotheses:

(chileftrightarrowpsi)
(phileftrightarrowpsi)

Assertions:

(phileftrightarrowchi)

Proof:

Hyp Ref Line Expr
Hypo1(chileftrightarrowpsi)
2(phileftrightarrowpsi)
1bicomi3(psileftrightarrowchi)
2, 3bitr4(phileftrightarrowchi)