title: how to get the result of adding the values of two text box inside angualrjs controller
body: <p>I want to get the result of adding to two text box value inside a controller </p>
  
  <pre><code>  &lt;div ng-app=""&gt;
  
          &lt;p&gt;First Number:
              &lt;input type="text" ng-model="a" /&gt;
          &lt;/p&gt;
          &lt;p&gt;Second Number:
              &lt;input type="text" ng-model="b" /&gt;
          &lt;/p&gt;
        &lt;p&gt;Second Number:
              &lt;input type="text" ng-model="a+b" /&gt;
          &lt;/p&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>i will get the value addded but if i use the expression in the model how to get in the controller </p>
  
  <p>and i am getting the error has ngModelSet is not a function</p>
  
  <p>As soon as the user enters the value in two textbox the result of adding two text box should be shown in the 3rd textbox and there is a submit button which give the value to controller how to do it please help</p>