centerbaseline=false
mml=<math xmlns="http://www.w3.org/1998/Math/MathML"><mover accent="false"><mi>XY</mi><mo>&#175;</mo></mover><mo>&#160;&#160;</mo><mo>+</mo><mi mathvariant="normal">&#160;</mi><mi>XY</mi><mi mathvariant="normal">&#160;</mi><mo>+</mo><mi mathvariant="normal">&#160;</mi><mi>YZ</mi></math>