Need to compare date with sysdate and put condition in the parameter in bip desktop

Hi

I have a requirement in BIP report(using bip desktop)where the condition would be

1. (Enddate<Startdate) and (Enddate<Startdate+5  or  Enddate=Startdate+5 ) and (Enddate<Sysdate)

I have declared two pareameters in the BIP rtf

$Startdate and $Enddate

I tried

a. <?if: ($Enddate-$Startdate<5 or $Enddate-$Startdate=5) and $Enddate>$Startdate ?>

b. <?if: ($Enddate<($Startdate+’5’) or $Enddate =($Startdate+’5’)) and  $Enddate>$Startdate ?>

But no result .I also cant compare the sysdate with the $Enddate also.

Please help.

Regards

Priyanka