set X = { x where x is Element of Funcs ({0,1},REAL) : x . 1 = 0 } ;
A2:
{(In (0,REAL)),1} c= REAL
by ZFMISC_1:32, Lm2;
rng ((0,1) --> (0,1)) c= {(In (0,REAL)),1}
by FUNCT_4:62, Lm1;
then
rng ((0,1) --> (0,1)) c= REAL
by A2, XBOOLE_1:1;
then
<i> is Relation of {0,1},REAL
by RELSET_1:6;
then
<i> in Funcs ({0,1},REAL)
by FUNCT_2:8;
then
<i> in (Funcs ({0,1},REAL)) \ { x where x is Element of Funcs ({0,1},REAL) : x . 1 = 0 }
by A1, XBOOLE_0:def 5;
hence
<i> in COMPLEX
by NUMBERS:def 2, XBOOLE_0:def 3; XCMPLX_0:def 2 verum