
<!DOCTYPE math
  PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<math xmlns="http://www.w3.org/1998/Math/MathML">
<apply>
  <product/>
  <bvar>
    <ci> x </ci>
  </bvar>
  <lowlimit>
    <ci> a </ci>
  </lowlimit>
  <uplimit>
    <ci> b </ci>
  </uplimit>
  <apply><ci type="fn"> f </ci>
    <ci> x </ci>
  </apply>
</apply>

<apply>
  <product/>
  <bvar>
    <ci> x </ci>
  </bvar>
  <condition>
    <apply> <in/>
      <ci> x </ci>
      <ci type="set"> B </ci>
    </apply>
  </condition>
  <apply><ci type="fn"> f </ci>
    <ci> x </ci>
  </apply>
</apply>
</math>