title: android studio 3.0.1 showing unable to merge dex why?
body: <p>I upgraded the android studio 2.x.x to android studio 3.0.1 after importing the project gradle building is successful. But when installing app showing the error message </p>
  
  <pre><code>Error:Execution failed for task ':app:transformDexArchiveWithExternalLibsDexMergerForDebug'.
  &gt; com.android.builder.dexing.DexArchiveMergerException: Unable to merge dex
  </code></pre>
  
  <p>my app grdle is given below</p>
  
  <p>Why it's showing this error and how to fix it? unable to install the app on the emulator.</p>
  
  <p>Already tried the clean and rebuild option in android studio but it doesn't fix the issue</p>