let G1, G2 be Function of T,R^1; ( ( for p being Point of T holds
( ( Rainbow (p,R) = {} implies G1 . p = 0 ) & ( for S being non empty Subset of ExtREAL st S = Rainbow (p,R) holds
G1 . p = sup S ) ) ) & ( for p being Point of T holds
( ( Rainbow (p,R) = {} implies G2 . p = 0 ) & ( for S being non empty Subset of ExtREAL st S = Rainbow (p,R) holds
G2 . p = sup S ) ) ) implies G1 = G2 )
assume that
A8:
for p being Point of T holds
( ( Rainbow (p,R) = {} implies G1 . p = 0 ) & ( for S being non empty Subset of ExtREAL st S = Rainbow (p,R) holds
G1 . p = sup S ) )
and
A9:
for p being Point of T holds
( ( Rainbow (p,R) = {} implies G2 . p = 0 ) & ( for S being non empty Subset of ExtREAL st S = Rainbow (p,R) holds
G2 . p = sup S ) )
; G1 = G2
for x being object st x in the carrier of T holds
G1 . x = G2 . x
hence
G1 = G2
by FUNCT_2:12; verum