let r, x0, x1, x2, x3, x4, x5 be Real; for f being Function of REAL,REAL holds [!(r (#) f),x0,x1,x2,x3,x4,x5!] = r * [!f,x0,x1,x2,x3,x4,x5!]
let f be Function of REAL,REAL; [!(r (#) f),x0,x1,x2,x3,x4,x5!] = r * [!f,x0,x1,x2,x3,x4,x5!]
[!(r (#) f),x0,x1,x2,x3,x4,x5!] =
((r * [!f,x0,x1,x2,x3,x4!]) - [!(r (#) f),x1,x2,x3,x4,x5!]) / (x0 - x5)
by Th11
.=
((r * [!f,x0,x1,x2,x3,x4!]) - (r * [!f,x1,x2,x3,x4,x5!])) / (x0 - x5)
by Th11
.=
(r * ([!f,x0,x1,x2,x3,x4!] - [!f,x1,x2,x3,x4,x5!])) / (x0 - x5)
;
hence
[!(r (#) f),x0,x1,x2,x3,x4,x5!] = r * [!f,x0,x1,x2,x3,x4,x5!]
by XCMPLX_1:74; verum