     functions of $x$. Give a formula (similar to the above) for
      $\dfrac{dR}{dx}.$</li>
    </ol>
  </div>

  <div class="problem">
    <div class="marginpar">
      <span class="larsonfive">See Larson 13.5:19&ndash;26 for more
      practice.</span>
    </div>

    <div class="marginpar">
      <span class="bmw">Make sure you practice problems 14.4:
      13-24. Use matrix multiplication, rather than the
      &ldquo;branch diagram&rdquo; referenced in the
      text.</span><span class="larsonfive">S