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<h2 id="Step-5:-Convergence">Step 5: Convergence<a class="anchor-link" href="#Step-5:-Convergence">&#182;</a></h2><ul>
<li><p>Choose a smooth solution <code>u</code> and calculate the right hand side <code>f</code> and boundary conditions for the unit square.</p>
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<li><p>Compute the error <code>uI - uh</code> in the maximum norm, where <co