<i>z</i>  denotes a <a href="https://en.wikipedia.org/wiki/Complex_number" class="extiw" title="w:Complex number">complex number</a>, defined by <a href="https://en.wiktionary.org/wiki/modulus#Noun" class="extiw" title="wiktionary:modulus">its modulus</a> equal to 1, <a href="https://en.wikipedia.org/wiki/Argument_(complex_analysis)" class="extiw" title="w:Argument (complex analysis)">and its argument</a>:  <span style="white-space:nowrap">arg( <i>z</i> ) = 150 degrees </span> modulo 360 degrees.
<a href="//commons.wikimedia.org/wiki/User:Baelde" title="User:Baelde">Baelde</a>
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