bv-∃mo

Theorem.

Arguments:

y (sv), phi (pr), x (sv),

Hypotheses:

(x bound in phi)

Assertions:

(x bound in _em1yphi)

Proof:

Hyp Ref Line Expr
Hypo1(x bound in phi)
1bv-∃12(x bound in _e1yphi)
1bv-∃3(x bound in existsyphi)
2, 3bv-→4(x bound in (existsyphito_e1yphi))
df-∃mo5(_em1yphileftrightarrow(existsyphito_e1yphi))
4, 5bvdef6(x bound in _em1yphi)