Example ex4-157

Prev: ex4-156

Next: ex4-158

f f

<math>
<apply>
  <eq/>
  <apply><laplacian/>
    <ci> f </ci>
  </apply>
  <apply>
    <divergence/>
    <apply><grad/>
      <ci> f </ci>
    </apply>
  </apply>
</apply>
</math>