1<?xml version='1.0'?> 2<!DOCTYPE html PUBLIC '-//W3C//DTD XHTML 1.1 plus MathML 2.0//EN' 3 'http://www.w3.org/TR/MathML2/dtd/xhtml-math11-f.dtd' 4 [<!ENTITY mathml 'http://www.w3.org/1998/Math/MathML'>]> 5<html xmlns='http://www.w3.org/1999/xhtml'> 6<head><title>trigamma4</title> 7<!-- MathML created with MathCast Equation Editor version 0.89 --> 8</head> 9<body> 10<math xmlns="http://www.w3.org/1998/Math/MathML" display="block"> 11 <mrow> 12 <msup> 13 <mi>ψ</mi> 14 <mfenced> 15 <mrow> 16 <mn>1</mn> 17 </mrow> 18 </mfenced> 19 </msup> 20 <mfenced> 21 <mrow> 22 <mi>x</mi> 23 </mrow> 24 </mfenced> 25 <mo>=</mo> 26 <mfrac> 27 <mrow> 28 <mfenced> 29 <mrow> 30 <mi>C</mi> 31 <mo>+</mo> 32 <mi>R</mi> 33 <mfenced> 34 <mrow> 35 <mi>x</mi> 36 </mrow> 37 </mfenced> 38 </mrow> 39 </mfenced> 40 </mrow> 41 <msup> 42 <mi>x</mi> 43 <mn>2</mn> 44 </msup> 45 </mfrac> 46 </mrow> 47</math> 48</body> 49</html>