A2:
Im f is_integrable_on M
by A1, Def4;
then A3:
-infty < Integral M,(Im f)
by MESFUNC6:90;
A4:
Re f is_integrable_on M
by A1, Def4;
then A5:
Integral M,(Re f) < +infty
by MESFUNC6:90;
A6:
Integral M,(Im f) < +infty
by A2, MESFUNC6:90;
-infty < Integral M,(Re f)
by A4, MESFUNC6:90;
then reconsider R = Integral M,(Re f), I = Integral M,(Im f) as Real by A5, A3, A6, XXREAL_0:14;
take IT = R + (I * <i> ); ex R, I being Real st
( R = Integral M,(Re f) & I = Integral M,(Im f) & IT = R + (I * <i> ) )
thus
ex R, I being Real st
( R = Integral M,(Re f) & I = Integral M,(Im f) & IT = R + (I * <i> ) )
; verum