Metamath Proof Explorer


Theorem xor2

Description: Two ways to express "exclusive or". (Contributed by Mario Carneiro, 4-Sep-2016)

Ref Expression
Assertion xor2 ( ( 𝜑𝜓 ) ↔ ( ( 𝜑𝜓 ) ∧ ¬ ( 𝜑𝜓 ) ) )

Proof

Step Hyp Ref Expression
1 df-xor ( ( 𝜑𝜓 ) ↔ ¬ ( 𝜑𝜓 ) )
2 nbi2 ( ¬ ( 𝜑𝜓 ) ↔ ( ( 𝜑𝜓 ) ∧ ¬ ( 𝜑𝜓 ) ) )
3 1 2 bitri ( ( 𝜑𝜓 ) ↔ ( ( 𝜑𝜓 ) ∧ ¬ ( 𝜑𝜓 ) ) )