let X be non empty set ; for S being SigmaField of X
for M being sigma_Measure of S
for f being PartFunc of X,REAL
for r being Real st f is_integrable_on M holds
( r (#) f is_integrable_on M & Integral (M,(r (#) f)) = r * (Integral (M,f)) )
let S be SigmaField of X; for M being sigma_Measure of S
for f being PartFunc of X,REAL
for r being Real st f is_integrable_on M holds
( r (#) f is_integrable_on M & Integral (M,(r (#) f)) = r * (Integral (M,f)) )
let M be sigma_Measure of S; for f being PartFunc of X,REAL
for r being Real st f is_integrable_on M holds
( r (#) f is_integrable_on M & Integral (M,(r (#) f)) = r * (Integral (M,f)) )
let f be PartFunc of X,REAL; for r being Real st f is_integrable_on M holds
( r (#) f is_integrable_on M & Integral (M,(r (#) f)) = r * (Integral (M,f)) )
let r be Real; ( f is_integrable_on M implies ( r (#) f is_integrable_on M & Integral (M,(r (#) f)) = r * (Integral (M,f)) ) )
assume
f is_integrable_on M
; ( r (#) f is_integrable_on M & Integral (M,(r (#) f)) = r * (Integral (M,f)) )
then A1:
R_EAL f is_integrable_on M
;
then
r (#) (R_EAL f) is_integrable_on M
by MESFUNC5:110;
then A2:
R_EAL (r (#) f) is_integrable_on M
by Th20;
Integral (M,(r (#) (R_EAL f))) = r * (Integral (M,(R_EAL f)))
by A1, MESFUNC5:110;
hence
( r (#) f is_integrable_on M & Integral (M,(r (#) f)) = r * (Integral (M,f)) )
by A2, Th20; verum