let f, g be Function of T,Y; ( ( for t being Point of T holds f . t = H . s,t ) & ( for t being Point of T holds g . t = H . s,t ) implies f = g )
assume that
A2:
for t being Point of T holds f . t = H . s,t
and
A3:
for t being Point of T holds g . t = H . s,t
; f = g
now let t be
Point of
T;
f . t = g . tthus f . t =
H . s,
t
by A2
.=
g . t
by A3
;
verum end;
hence
f = g
by FUNCT_2:113; verum