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Axiom ax-9d1 2297
Description: Distinct variable version of ax9 1949, equal variables case. (Contributed by Mario Carneiro, 14-Aug-2015.)
Assertion
Ref Expression
ax-9d1 ¬ x ¬ x = x

Detailed syntax breakdown of Axiom ax-9d1
StepHypRef Expression
1 vx . . . . 5 setvar x
21, 1weq 1643 . . . 4 wff x = x
32wn 3 . . 3 wff ¬ x = x
43, 1wal 1540 . 2 wff x ¬ x = x
54wn 3 1 wff ¬ x ¬ x = x
Colors of variables: wff setvar class
This axiom is referenced by: (None)
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