Description: 4 - 1 = 3. (Contributed by AV, 8-Feb-2021) (Proof shortened by AV, 6-Sep-2021)
Ref | Expression | ||
---|---|---|---|
Assertion | 4m1e3 | |- ( 4 - 1 ) = 3 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | 3cn | |- 3 e. CC |
|
2 | ax-1cn | |- 1 e. CC |
|
3 | df-4 | |- 4 = ( 3 + 1 ) |
|
4 | 1 2 3 | mvrraddi | |- ( 4 - 1 ) = 3 |