1<math xmlns="http://www.w3.org/1998/Math/MathML" display="block"> 2 <mrow> 3 <mtext>erfc</mtext> 4 <mfenced> 5 <mrow> 6 <mi>z</mi> 7 </mrow> 8 </mfenced> 9 <mspace width="1em"/> 10 <mo>=</mo> 11 <mspace width="1em"/> 12 <mn>1</mn> 13 <mo>−</mo> 14 <mtext>erf</mtext> 15 <mfenced> 16 <mrow> 17 <mi>z</mi> 18 </mrow> 19 </mfenced> 20 </mrow> 21</math> 22 23