Example ex4-121

Prev: ex4-120

Next: ex4-122

x f x 0

<math>
<apply>
  <exists/>
  <bvar><ci> x </ci></bvar>
  <apply><eq/>
    <apply>
      <fn><ci> f </ci></fn>
      <ci> x </ci>
    </apply>
    <cn>0</cn>
  </apply>
</apply>
</math>