let it1, it2 be Function of [:REAL ,(PFuncs A,REAL ):],(PFuncs A,REAL ); ( ( for a being Real
for f being Element of PFuncs A,REAL holds it1 . a,f = a (#) f ) & ( for a being Real
for f being Element of PFuncs A,REAL holds it2 . a,f = a (#) f ) implies it1 = it2 )
assume that
A1:
for a being Real
for f being Element of PFuncs A,REAL holds it1 . a,f = a (#) f
and
A2:
for a being Real
for f being Element of PFuncs A,REAL holds it2 . a,f = a (#) f
; it1 = it2
hence
it1 = it2
by BINOP_1:2; verum