let D, C be non empty set ; for F being PartFunc of D,REAL
for G being PartFunc of C,REAL holds
( F,G are_fiberwise_equipotent iff - F, - G are_fiberwise_equipotent )
let F be PartFunc of D,REAL ; for G being PartFunc of C,REAL holds
( F,G are_fiberwise_equipotent iff - F, - G are_fiberwise_equipotent )
let G be PartFunc of C,REAL ; ( F,G are_fiberwise_equipotent iff - F, - G are_fiberwise_equipotent )
- F = (- 1) (#) F
;
hence
( F,G are_fiberwise_equipotent iff - F, - G are_fiberwise_equipotent )
by Th13; verum