How to get x of 2^x=8000?
<blockquote>
  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/4016213/whats-the-opposite-of-javascripts-math-pow">What&#39;s the opposite of JavaScript&#39;s Math.pow?</a>  </p>
</blockquote>



<pre><code>2^x=i
</code></pre>

<p>Given i, how can we calculate x using Javascript?</p>
