ig.html" class="external-link">cos</a></span><span class="op">(</span><span class="fl">2</span><span class="op">*</span><span class="va">x</span><span class="op">)</span><span class="op">*</span><span class="fl">0.5</span><span class="op">*</span><span class="fu"><a href="https://rdrr.io/r/base/Trig.html" class="external-link">sin</a></span><span class="op">(</span><span class="fl">3</span><span class="op">*</span><span class="va">y</span><span class="op">)</span> <span class="op">+</span> </span>
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