let V be ComplexLinearSpace; for v being VECTOR of V
for L being C_Linear_Combination of V st L is convex & Carrier L = {v} holds
( ex r being Real st
( r = L . v & r = 1 ) & Sum L = (L . v) * v )
let v be VECTOR of V; for L being C_Linear_Combination of V st L is convex & Carrier L = {v} holds
( ex r being Real st
( r = L . v & r = 1 ) & Sum L = (L . v) * v )
let L be C_Linear_Combination of V; ( L is convex & Carrier L = {v} implies ( ex r being Real st
( r = L . v & r = 1 ) & Sum L = (L . v) * v ) )
assume that
A1:
L is convex
and
A2:
Carrier L = {v}
; ( ex r being Real st
( r = L . v & r = 1 ) & Sum L = (L . v) * v )
reconsider L = L as C_Linear_Combination of {v} by A2, Def4;
consider F being FinSequence of the carrier of V such that
A3:
( F is one-to-one & rng F = Carrier L )
and
A4:
ex f being FinSequence of REAL st
( len f = len F & Sum f = 1 & ( for n being Nat st n in dom f holds
( f . n = L . (F . n) & f . n >= 0 ) ) )
by A1;
A5:
F = <*v*>
by A2, A3, FINSEQ_3:97;
consider f being FinSequence of REAL such that
A6:
len f = len F
and
A7:
Sum f = 1
and
A8:
for n being Nat st n in dom f holds
( f . n = L . (F . n) & f . n >= 0 )
by A4;
reconsider r = f /. 1 as Element of REAL ;
card (Carrier L) = 1
by A2, CARD_1:30;
then
len F = 1
by A3, FINSEQ_4:62;
then A9:
dom f = Seg 1
by A6, FINSEQ_1:def 3;
then A10:
1 in dom f
;
then A11:
f . 1 = f /. 1
by PARTFUN1:def 6;
then A12:
f = <*r*>
by A9, FINSEQ_1:def 8;
f . 1 = L . (F . 1)
by A8, A10;
then
r = L . v
by A11, A5, FINSEQ_1:def 8;
hence
( ex r being Real st
( r = L . v & r = 1 ) & Sum L = (L . v) * v )
by A7, A12, Th14, FINSOP_1:11; verum