bexim<

Theorem.

Arguments:

x (sv), phi (pr), psi (pr),

Hypotheses:

(x bound in phi)

Assertions:

(existsx(phitopsi)leftrightarrow(phitoexistsxpsi))

Proof:

Hyp Ref Line Expr
Hypo1(x bound in phi)
bexim2(existsx(phitopsi)leftrightarrow(forallxphitoexistsxpsi))
1fv.eqal3(phileftrightarrowforallxphi)
3bi.bldim<4((phitoexistsxpsi)leftrightarrow(forallxphitoexistsxpsi))
2, 4><bitr5(existsx(phitopsi)leftrightarrow(phitoexistsxpsi))