let n be Element of NAT ; for h, r, x being Real
for f1, f2 being Function of REAL,REAL holds ((bdif (((r (#) f1) + f2),h)) . (n + 1)) . x = (r * (((bdif (f1,h)) . (n + 1)) . x)) + (((bdif (f2,h)) . (n + 1)) . x)
let h, r, x be Real; for f1, f2 being Function of REAL,REAL holds ((bdif (((r (#) f1) + f2),h)) . (n + 1)) . x = (r * (((bdif (f1,h)) . (n + 1)) . x)) + (((bdif (f2,h)) . (n + 1)) . x)
let f1, f2 be Function of REAL,REAL; ((bdif (((r (#) f1) + f2),h)) . (n + 1)) . x = (r * (((bdif (f1,h)) . (n + 1)) . x)) + (((bdif (f2,h)) . (n + 1)) . x)
set g = r (#) f1;
((bdif (((r (#) f1) + f2),h)) . (n + 1)) . x =
(((bdif ((r (#) f1),h)) . (n + 1)) . x) + (((bdif (f2,h)) . (n + 1)) . x)
by DIFF_1:15
.=
(r * (((bdif (f1,h)) . (n + 1)) . x)) + (((bdif (f2,h)) . (n + 1)) . x)
by DIFF_1:14
;
hence
((bdif (((r (#) f1) + f2),h)) . (n + 1)) . x = (r * (((bdif (f1,h)) . (n + 1)) . x)) + (((bdif (f2,h)) . (n + 1)) . x)
; verum