Description: Closure of square. (Contributed by NM, 10-Aug-1999)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | sqcl | |- ( A e. CC -> ( A ^ 2 ) e. CC ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | sqval | |- ( A e. CC -> ( A ^ 2 ) = ( A x. A ) ) |
|
| 2 | mulcl | |- ( ( A e. CC /\ A e. CC ) -> ( A x. A ) e. CC ) |
|
| 3 | 2 | anidms | |- ( A e. CC -> ( A x. A ) e. CC ) |
| 4 | 1 3 | eqeltrd | |- ( A e. CC -> ( A ^ 2 ) e. CC ) |