<<< native
[ ESymbol Op "\8747"
, EIdentifier "f"
, EDelimited "(" ")" [ Right (EIdentifier "x") ]
, ESpace (1 % 9)
, ESymbol Ord "\8518"
, EIdentifier "x"
]
>>> omml
<?xml version='1.0' ?>
<m:oMathPara>
  <m:oMathParaPr>
    <m:jc m:val="center" />
  </m:oMathParaPr>
  <m:oMath>
    <m:r>
      <m:rPr>
        <m:sty m:val="p" />
      </m:rPr>
      <m:t>∫</m:t>
    </m:r>
    <m:r>
      <m:t>f</m:t>
    </m:r>
    <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>x</m:t>
        </m:r>
      </m:e>
    </m:d>
    <m:r>
      <m:t> </m:t>
    </m:r>
    <m:r>
      <m:rPr>
        <m:sty m:val="p" />
      </m:rPr>
      <m:t>ⅆ</m:t>
    </m:r>
    <m:r>
      <m:t>x</m:t>
    </m:r>
  </m:oMath>
</m:oMathPara>