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      <mal:name>Christopher Meng</mal:name>
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      <mal:years>2012-2013</mal:years>
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    <mal:credit xmlns:mal="http://projectmallard.org/1.0/" type="translator copyright">
      <mal:name>ravix</mal:name>
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      <mal:years>2013</mal:years>
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    <mal:credit xmlns:mal="http://projectmallard.org/1.0/" type="translator copyright">
      <mal:name>Dianjin Wang</mal:name>
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      <mal:years>2012</mal:years>
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    <mal:credit xmlns:mal="http://projectmallard.org/1.0/" type="translator copyright">
      <mal:name>Cravix</mal:name>
      <mal:email>dr.neemous@gmail.com</mal:email>
      <mal:years>2013</mal:years>
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    <mal:credit xmlns:mal="http://projectmallard.org/1.0/" type="translator copyright">
      <mal:name>nyanyh</mal:name>
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      <mal:years>2013</mal:years>
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    <mal:credit xmlns:mal="http://projectmallard.org/1.0/" type="translator copyright">
      <mal:name>liulitchi</mal:name>
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      <mal:years>2013</mal:years>
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    <mal:credit xmlns:mal="http://projectmallard.org/1.0/" type="translator copyright">
      <mal:name>玉堂白鹤</mal:name>
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      <mal:years>2015</mal:years>
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    <mal:credit xmlns:mal="http://projectmallard.org/1.0/" type="translator copyright">
      <mal:name>Mingye Wang</mal:name>
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      <mal:years>2015-2016</mal:years>
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    <mal:credit xmlns:mal="http://projectmallard.org/1.0/" type="translator copyright">
      <mal:name>白铭骢</mal:name>
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      <mal:years>2015-2016</mal:years>
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    <mal:credit xmlns:mal="http://projectmallard.org/1.0/" type="translator copyright">
      <mal:name>刘子兴</mal:name>
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      <mal:years>2015-2016</mal:years>
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	<title>Trigonometry</title>
    
    <p>
    Trigonometry can be performed using the sin, cos, and tan <link xref="function">function</link>.
    </p>
    <example>
    <p>
    sin 45
    </p>
    </example>
    <p>
    The angle units used can be changed from the <guiseq><gui>Calculator</gui><gui>Preferences</gui></guiseq> menu.
    Trigonometry buttons are visible when in <link xref="mouse">Advanced mode</link>.
    </p>
    <p>
    Hyperbolic functions are available by adding "h" to the end of a function.
    </p>
    <example>
    <p>
    sinh 0.34
    </p>
    </example>
    <p>
    Inverse functions are entered either using the inverse symbol ⁻¹ (<keyseq><key>Ctrl</key><key>I</key></keyseq>) or the "a" form of the function.
    The following two equations are equivalent.
    </p>
    <example>
    <p>
    sin⁻¹ 0.5
    </p>
    <p>
    asin 0.5 
    </p>
    </example>   
    <p>
    To enter <link xref="variable">π</link> with the keyboard use <keyseq><key>Ctrl</key><key>P</key></keyseq>.
    </p>
</page>
