deffunc H1( Real, Element of REAL n) -> Element of REAL n = $1 * $2;
consider f being Function of [:REAL,(REAL n):],(REAL n) such that
A1:
for r being Element of REAL
for x being Element of REAL n holds f . (r,x) = H1(r,x)
from BINOP_1:sch 4();
take
f
; for r being Real
for x being Element of REAL n holds f . (r,x) = r * x
let r be Real; for x being Element of REAL n holds f . (r,x) = r * x
let x be Element of REAL n; f . (r,x) = r * x
reconsider r = r as Element of REAL by XREAL_0:def 1;
f . (r,x) = H1(r,x)
by A1;
hence
f . (r,x) = r * x
; verum