Description: The absolute value of an integer is an integer. (Contributed by Stefan O'Rear, 24-Sep-2014)
Ref | Expression | ||
---|---|---|---|
Assertion | zabscl | |- ( A e. ZZ -> ( abs ` A ) e. ZZ ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | nn0abscl | |- ( A e. ZZ -> ( abs ` A ) e. NN0 ) |
|
2 | 1 | nn0zd | |- ( A e. ZZ -> ( abs ` A ) e. ZZ ) |