Description: 0 is a left identity for addition. (Contributed by NM, 3-Jan-2013)
Ref | Expression | ||
---|---|---|---|
Hypothesis | mul.1 | $${\u22a2}{A}\in \u2102$$ | |
Assertion | addid2i | $${\u22a2}0+{A}={A}$$ |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | mul.1 | $${\u22a2}{A}\in \u2102$$ | |
2 | addid2 | $${\u22a2}{A}\in \u2102\to 0+{A}={A}$$ | |
3 | 1 2 | ax-mp | $${\u22a2}0+{A}={A}$$ |