Description: XOR implies NAND (written with the -/\ connector). (Contributed by BJ, 19-Apr-2019)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | xornan2 | ⊢ ( ( 𝜑 ⊻ 𝜓 ) → ( 𝜑 ⊼ 𝜓 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | xornan | ⊢ ( ( 𝜑 ⊻ 𝜓 ) → ¬ ( 𝜑 ∧ 𝜓 ) ) | |
| 2 | df-nan | ⊢ ( ( 𝜑 ⊼ 𝜓 ) ↔ ¬ ( 𝜑 ∧ 𝜓 ) ) | |
| 3 | 1 2 | sylibr | ⊢ ( ( 𝜑 ⊻ 𝜓 ) → ( 𝜑 ⊼ 𝜓 ) ) |