let X be set ; :: thesis: for f being PartFunc of COMPLEX ,COMPLEX st f is_continuous_on X holds
- f is_continuous_on X
let f be PartFunc of COMPLEX ,COMPLEX ; :: thesis: ( f is_continuous_on X implies - f is_continuous_on X )
assume A1: f is_continuous_on X ; :: thesis: - f is_continuous_on X
- f = (- 1r ) (#) f by CFUNCT_1:40;
hence - f is_continuous_on X by A1, Th67; :: thesis: verum