Description: Add a zero in the higher places. (Contributed by Mario Carneiro, 18-Feb-2014)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | numnncl.1 | |- T e. NN0  | 
					|
| numnncl.2 | |- A e. NN0  | 
					||
| Assertion | num0h | |- A = ( ( T x. 0 ) + A )  | 
				
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | numnncl.1 | |- T e. NN0  | 
						|
| 2 | numnncl.2 | |- A e. NN0  | 
						|
| 3 | 1 | nn0cni | |- T e. CC  | 
						
| 4 | 3 | mul01i | |- ( T x. 0 ) = 0  | 
						
| 5 | 4 | oveq1i | |- ( ( T x. 0 ) + A ) = ( 0 + A )  | 
						
| 6 | 2 | nn0cni | |- A e. CC  | 
						
| 7 | 6 | addlidi | |- ( 0 + A ) = A  | 
						
| 8 | 5 7 | eqtr2i | |- A = ( ( T x. 0 ) + A )  |