Description: A -/\ identity. (Contributed by Anthony Hart, 23-Oct-2010) (Proof shortened by Andrew Salmon, 13-May-2011)
Ref | Expression | ||
---|---|---|---|
Assertion | falnantru | ⊢ ( ( ⊥ ⊼ ⊤ ) ↔ ⊤ ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nancom | ⊢ ( ( ⊥ ⊼ ⊤ ) ↔ ( ⊤ ⊼ ⊥ ) ) | |
2 | trunanfal | ⊢ ( ( ⊤ ⊼ ⊥ ) ↔ ⊤ ) | |
3 | 1 2 | bitri | ⊢ ( ( ⊥ ⊼ ⊤ ) ↔ ⊤ ) |