<<< native
[ ESub (EIdentifier "S") (EText TextNormal "new")
, ESymbol Rel "="
, ESub (EIdentifier "S") (EText TextNormal "old")
, ESymbol Bin "\8722"
, EFraction
    NormalFrac
    (ESuper
       (EDelimited
          "("
          ")"
          [ Right (ENumber "5")
          , Right (ESymbol Bin "\8722")
          , Right (EIdentifier "T")
          ])
       (ENumber "2"))
    (ENumber "2")
]
>>> omml
<?xml version='1.0' ?>
<m:oMathPara>
  <m:oMathParaPr>
    <m:jc m:val="center" />
  </m:oMathParaPr>
  <m:oMath>
    <m:sSub>
      <m:e>
        <m:r>
          <m:t>S</m:t>
        </m:r>
      </m:e>
      <m:sub>
        <m:r>
          <m:rPr>
            <m:nor />
            <m:sty m:val="p" />
          </m:rPr>
          <m:t>new</m:t>
        </m:r>
      </m:sub>
    </m:sSub>
    <m:r>
      <m:rPr>
        <m:sty m:val="p" />
      </m:rPr>
      <m:t>=</m:t>
    </m:r>
    <m:sSub>
      <m:e>
        <m:r>
          <m:t>S</m:t>
        </m:r>
      </m:e>
      <m:sub>
        <m:r>
          <m:rPr>
            <m:nor />
            <m:sty m:val="p" />
          </m:rPr>
          <m:t>old</m:t>
        </m:r>
      </m:sub>
    </m:sSub>
    <m:r>
      <m:rPr>
        <m:sty m:val="p" />
      </m:rPr>
      <m:t>−</m:t>
    </m:r>
    <m:f>
      <m:fPr>
        <m:type m:val="bar" />
      </m:fPr>
      <m:num>
        <m:sSup>
          <m:e>
            <m:d>
              <m:dPr>
                <m:begChr m:val="(" />
                <m:endChr m:val=")" />
                <m:sepChr m:val="" />
                <m:grow />
              </m:dPr>
              <m:e>
                <m:r>
                  <m:t>5</m:t>
                </m:r>
                <m:r>
                  <m:rPr>
                    <m:sty m:val="p" />
                  </m:rPr>
                  <m:t>−</m:t>
                </m:r>
                <m:r>
                  <m:t>T</m:t>
                </m:r>
              </m:e>
            </m:d>
          </m:e>
          <m:sup>
            <m:r>
              <m:t>2</m:t>
            </m:r>
          </m:sup>
        </m:sSup>
      </m:num>
      <m:den>
        <m:r>
          <m:t>2</m:t>
        </m:r>
      </m:den>
    </m:f>
  </m:oMath>
</m:oMathPara>