title: Why do I get a wrong result for this calculation in my android app?
body: <p>In my app i am using this to calculate a number:</p>
  
  <pre><code>double result = ((a * a) + (b * b) - (2 * a * b));
  </code></pre>
  
  <p>If a for example a = 2 and b = 3.9, then the result should be 3.61. However, when I display "result" i get the number 3.610000000000001.</p>
  
  <p>What is wrong here? How can I correct this error?</p>