let A be non empty closed_interval Subset of REAL; for D being Division of A
for rho being Function of A,REAL
for B being non empty closed_interval Subset of REAL
for v being FinSequence of REAL st B c= A & len D = len v & ( for i being Nat st i in dom v holds
v . i = vol ((B /\ (divset (D,i))),rho) ) holds
Sum v = vol (B,rho)
let D be Division of A; for rho being Function of A,REAL
for B being non empty closed_interval Subset of REAL
for v being FinSequence of REAL st B c= A & len D = len v & ( for i being Nat st i in dom v holds
v . i = vol ((B /\ (divset (D,i))),rho) ) holds
Sum v = vol (B,rho)
let rho be Function of A,REAL; for B being non empty closed_interval Subset of REAL
for v being FinSequence of REAL st B c= A & len D = len v & ( for i being Nat st i in dom v holds
v . i = vol ((B /\ (divset (D,i))),rho) ) holds
Sum v = vol (B,rho)
let B be non empty closed_interval Subset of REAL; for v being FinSequence of REAL st B c= A & len D = len v & ( for i being Nat st i in dom v holds
v . i = vol ((B /\ (divset (D,i))),rho) ) holds
Sum v = vol (B,rho)
let v be FinSequence of REAL ; ( B c= A & len D = len v & ( for i being Nat st i in dom v holds
v . i = vol ((B /\ (divset (D,i))),rho) ) implies Sum v = vol (B,rho) )
assume AS:
( B c= A & len D = len v & ( for i being Nat st i in dom v holds
v . i = vol ((B /\ (divset (D,i))),rho) ) )
; Sum v = vol (B,rho)
dom rho = A
by FUNCT_2:def 1;
hence
Sum v = vol (B,rho)
by AS, LmINTEGR208; verum