title: How to find only the first and last line of a file using sed
body: <p>I have a file called <code>error_log</code> for the apache and I want to see the first line and the last line of this file using <code>sed</code> command. Would you please help me how can I do that?</p>
  <p>I know how to do that with <code>head</code> and <code>tail</code> commands, but I'm curious if it's possible in <code>sed</code> command too.</p>
  <p>I have read the <code>man sed</code> and have googled a lot but nothing is found unfortunately.</p>