If you're prepared to modify the way you input your function -- ie. use * instead of implied multiplication; add brackets to functions etc -- then something like this might get you started:

sub genFunc{ 
    my $expr = shift; 
    $expr =~ s[x][\$x]g; 
    print "'$expr'"; 
    return eval "sub{ my \$x = shift; return $expr; }"; 
};;

my $f = genFunc( '(1-x)/(sin()**2*(2*x))' );;
'(1-$x)/(sin()**2*(2*$x))'

print "$_: ", $f->( $_ ) for 1 .. 10;;
1:  0
2:  -0.302362609265759
3:  -16.7379227868029
4:  -0.65473590385359
5:  -0.435002112398393
6:  -5.33688415389075
7:  -0.992910704853273
8:  -0.446962308202578
9:  -2.61681663614942
10:  -1.52048103620111
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Note: I'm fully aware that my attempt at modifying your function is wrong (sin() with out an argument?), but I couldn't make better sense of your intent.