Description: Equality implies inclusion. (Contributed by NM, 21-Jun-1993) (Proof shortened by Andrew Salmon, 21-Jun-2011)
Ref | Expression | ||
---|---|---|---|
Assertion | eqimss | ⊢ ( 𝐴 = 𝐵 → 𝐴 ⊆ 𝐵 ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | id | ⊢ ( 𝐴 = 𝐵 → 𝐴 = 𝐵 ) | |
2 | 1 | eqimssd | ⊢ ( 𝐴 = 𝐵 → 𝐴 ⊆ 𝐵 ) |