jQuery: Setting attribute required for input tag

jQuery: Setting attribute required for input tag

I was trying to set attribute to an input tag using jQuery. All other
attributes for input tag like maxlength,name,class worked well. But i'm
having trouble with required attribute.
I tried this way
$("<label><strong>Class"+fare+"</strong></label><input type='text'
value='' />")
.attr("class", "nameval") .attr("name", "class"+fare+"")
.attr("required","required")
I also tried other ways refering to some forums
.attr("required","")
.attr("required",true)
.attr("required","true")
.prop("required",true)
Please let me know where i was wrong.