theorem zmul12 (a: nat): $ a *Z b0 1 = a $;
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | eqtr | a *Z b0 1 = b0 1 *Z a -> b0 1 *Z a = a -> a *Z b0 1 = a |
|
2 | zmulcom | a *Z b0 1 = b0 1 *Z a |
|
3 | 1, 2 | ax_mp | b0 1 *Z a = a -> a *Z b0 1 = a |
4 | zmul11 | b0 1 *Z a = a |
|
5 | 3, 4 | ax_mp | a *Z b0 1 = a |