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<div class="container">
<table class="table table-striped">
<tr><th>θ[deg]</th><th>sin(θ)</th><th>cos(θ)</th><th>tan(θ)</th></tr>
<tr data-toggle="collapse" data-target="#tr_a" aria-expanded="false" aria-controls="tr_a">
<td>0</td><td>0</td><td>1</td><td>0</td>
</tr>
<tr id="tr_a" class="collapse">
<td>15</td><td>0.2588</td><td>0.9659</td><td>0.2679</td>
</tr>
<tr data-toggle="collapse" data-target="#tr_b" aria-expanded="false" aria-controls="tr_b">
<td>30</td><td>0.5000</td><td>0.8660</td><td>0.5774</td>
</tr>
<tr id="tr_b" class="collapse">
<td>45</td><td>0.7071</td><td>0.7071</td><td>1.0000</td>
</tr>
</table>
</div>
