arctan2

arctan(x(y + z)z)

W3C sample	WIRIS
[N/A]	$arctan times x plus y z z$

<math xmlns="http://www.w3.org/1998/Math/MathML">
  <apply>
    <csymbol cd="transc1">arctan</csymbol>
    <apply>
      <csymbol cd="arith1">times</csymbol>
      <ci>x</ci>
      <apply>
        <csymbol cd="arith1">plus</csymbol>
        <ci>y</ci>
        <ci>z</ci>
      </apply>
      <ci>z</ci>
    </apply>
  </apply>
</math>

Author: Design Science, Inc. (E. Cannon, E. Tabacman, R.Miner)