ax9ex

Theorem.

Arguments:

x (sv), y (st),

Distinct variable conditions:

(x, y),

Assertions:

existsx(xeqy)

Proof:

Hyp Ref Line Expr
ax91lnotforallxlnot(xeqy)
df-ex2(existsx(xeqy)leftrightarrowlnotforallxlnot(xeqy))
1, 2bmp<3existsx(xeqy)