Description: An integer modulo 1 is 0. (Contributed by Paul Chapman, 22-Jun-2011)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | zmod10 | |- ( N e. ZZ -> ( N mod 1 ) = 0 ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | zre | |- ( N e. ZZ -> N e. RR ) | |
| 2 | modfrac | |- ( N e. RR -> ( N mod 1 ) = ( N - ( |_ ` N ) ) ) | |
| 3 | 1 2 | syl | |- ( N e. ZZ -> ( N mod 1 ) = ( N - ( |_ ` N ) ) ) | 
| 4 | flid | |- ( N e. ZZ -> ( |_ ` N ) = N ) | |
| 5 | 4 | oveq2d | |- ( N e. ZZ -> ( N - ( |_ ` N ) ) = ( N - N ) ) | 
| 6 | zcn | |- ( N e. ZZ -> N e. CC ) | |
| 7 | 6 | subidd | |- ( N e. ZZ -> ( N - N ) = 0 ) | 
| 8 | 3 5 7 | 3eqtrd | |- ( N e. ZZ -> ( N mod 1 ) = 0 ) |