theorem :: MESFUN15:77

for f being PartFunc of REAL,REAL
for a, b being Real st a < b & [.a,b.[ c= dom f & f is_right_improper_integrable_on a,b & abs f is_right_ext_Riemann_integrable_on a,b holds
max+ f is_right_ext_Riemann_integrable_on a,b