title: MATLAB solver gives empty vector
body: <p>I am getting unexpected behavior and I'm not sure where to start.</p>
  <p>I have a simple polynomial</p>
  <p><code>20/[(s(s+1)]</code></p>
  <p>and I need to replace <code>s</code> with <code>jω</code>, take its absolute value, convert it to <code>dB</code> and then solve for <code>ω</code> by setting this equal to a known value.</p>
  <pre><code>syms w
  
  Omega = double(solve(20*log10(abs((20)/(1i*w*(1i*w+1)))) == -desired_db, w));
  </code></pre>
  <p>Yet, when I go to solve it I get results that I can't make sense of. It's saying it is an empty space column vector. According to our professor, the answer should be about 6.7</p>
  <p>Any thoughts?</p>