How to get first date and last date of the week from week number and year?

Question

In JavaScript I want to get first date of the week and last date of the week by week number and year only.

For example if I my input is:

2(week),2012

Answer 1

   dt = new Date();
   var firstDateOfWeek=(dt.setDate(dt.getDate()-dt.getDay()));
   var lastDateOfWeek=(dt.setDate(dt.getDate()+6-dt.getDay()));