centerbaseline=false
mml=<math xmlns="http://www.w3.org/1998/Math/MathML"><mi>f</mi><mfenced><mi>x</mi></mfenced><mo>=</mo><mi>cos</mi><mfenced><mrow><mn>2</mn><mi>x</mi><mo>-</mo><mfrac><mi mathvariant="normal">π</mi><mn>6</mn></mfrac></mrow></mfenced></math>
