Description: Identity law for multiplication. (Contributed by Mario Carneiro, 27-May-2016)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | addcld.1 | |- ( ph -> A e. CC ) |
|
| Assertion | mulridd | |- ( ph -> ( A x. 1 ) = A ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | addcld.1 | |- ( ph -> A e. CC ) |
|
| 2 | mulrid | |- ( A e. CC -> ( A x. 1 ) = A ) |
|
| 3 | 1 2 | syl | |- ( ph -> ( A x. 1 ) = A ) |