minus7

- ( (a + b) / (a - b) )

W3C sample	WIRIS
	$-\left(\frac{a+b}{a-b}\right)$

<math xmlns="http://www.w3.org/1998/Math/MathML">
  <apply>
    <minus/>
    <apply>
      <divide/>
      <apply>
        <plus/>
        <ci>a</ci>
        <ci>b</ci>
      </apply>
      <apply>
        <minus/>
        <ci>a</ci>
        <ci>b</ci>
      </apply>
    </apply>
  </apply>
</math>

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