title: sum two dates in node.js?
body: <p>i'm trying to sum two dates. </p>
  
  <p>date1 and date2 are Date() objects.</p>
  
  <p>i read oher questions and googled it.. i tryed this way but it return a negative number </p>
  
  <pre><code>var sum_millis = date1.getTime()+date2.getTime();
  
  var sum=new Date(sum_millis);
  
  console.log(sum.toString());
  </code></pre>
  
  <p>date1:  1901-02-01T00:10:00.000Z</p>
  
  <p>date2:  1901-01-31T23:07:23.000Z</p>
  
  <p>result:  -4349551357000</p>
  
  <p>what i'm doing wrong? </p>