This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: Add a zero in the higher places. (Contributed by Mario Carneiro, 18-Feb-2014)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | numnncl.1 | ||
| numnncl.2 | |||
| Assertion | num0h |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | numnncl.1 | ||
| 2 | numnncl.2 | ||
| 3 | 1 | nn0cni | |
| 4 | 3 | mul01i | |
| 5 | 4 | oveq1i | |
| 6 | 2 | nn0cni | |
| 7 | 6 | addlidi | |
| 8 | 5 7 | eqtr2i |