Right hand side of equation should look like mirrored copy of left hand side
<math xmlns="http://www.w3.org/1998/Math/MathML" display="block"> <mfenced open="{" close="|"> <mrow> <mtable> <mtr> <mtd> <mi mathvariant="normal">U</mi> </mtd> </mtr> <mtr> <mtd> <mi mathvariant="normal">V</mi> </mtd> </mtr> </mtable> </mrow> </mfenced> <mo>=</mo> <mfenced open="|" close="}"> <mrow> <mtable> <mtr> <mtd> <mi mathvariant="normal">U</mi> </mtd> </mtr> <mtr> <mtd> <mi mathvariant="normal">V</mi> </mtd> </mtr> </mtable> </mrow> </mfenced> </math>