How can I check tautology or not using recursion
<p>I have problem with my code. I need to check tautology using recursion. Please give me some hint. 
I know how recursion works. But I do not have clue how to apply in tautology. 
this is my arbitrary. </p>

<p><code>((p | q) &amp; !(p &amp; q)) == (p | q);</code> </p>

<p>I want to check something like this.
Please help me!</p>
