\!\(\*
  RowBox[{
    RowBox[{"(*", " ",
      StyleBox[\(Ejercicio\ 42\),
        FontColor->RGBColor[1, 0, 0]], " ", "*)"}], "\n",
    \( (*\ Deducir\ los\ conmutadores\
        \(siguientes : \n\t\t\ \([lx, \ y]\)\ y\ [lz, \ z]\)\ *) \),
"\n",
    \( (*\ \([lx, y]\)\ *) \), "\n",
    \( (*\ lx = \(-\[ImaginaryI]h\) \((y*d\/dz - z*d\/dy)\)\ *) \),
"\n",
    \( (*\ \([\(-\[ImaginaryI]h\) \((y*d\/dz - z*d\/dy)\), y]\)\ *) \),
    "\n",
    RowBox[{
    \(ClearAll["\<Global`*\>"]\), "\n",
      \(A = \(-\[ImaginaryI]\)*h \((y*D[y\ f[x], z] - z*D[y\ f[x],
y])\)\),
      "\n", \(I\ h\ z\ f[x]\), "\n",
      \(B = \(-\[ImaginaryI]\)\ h\ y
          \((y*\ D[\ f[x], z] - z*\ D[f[x], y])\)\), "\n", "0", "\n",
      \((A - B)\), "\n", \(I\ h\ z\ f[x]\), "\n", \(\((A - B)\)/f[x]\),
"\n",
      \(I\ h\ z\), "\n", \( (*\ lz, z\ *) \), "\n",
      \( (*\ lz = \(-\[ImaginaryI]h\) \((x*d\/dy - y*d\/dx)\)\ *) \),
"\n",
      \( (*\ \([\(-\[ImaginaryI]h\) \((x*d\/dy - y*d\/dx)\), y]\)\ *)
\),
      "\n", \(ClearAll["\<Global`*\>"]\), "\n",
      \(A = \(-\[ImaginaryI]\)*h \((x*D[z\ f[x], y] - y*D[z\ f[x],
x])\)\),
      "\n",
      RowBox[{"I", " ", "h", " ", "y", " ", "z", " ",
        RowBox[{
          SuperscriptBox["f", "\[Prime]",
            MultilineFunction->None], "[", "x", "]"}]}], "\n",
      \(B = \(-\[ImaginaryI]\)\ h\ z
          \((x*\ D[\ f[x], y] - y*\ D[f[x], x])\)\), "\n",
      RowBox[{"I", " ", "h", " ", "y", " ", "z", " ",
        RowBox[{
          SuperscriptBox["f", "\[Prime]",
            MultilineFunction->None], "[", "x", "]"}]}], "\n", \((A -
B)\),
      "\n", "0", "\n", \(\((A - B)\)/f[x]\), "\n", "0"}], "\n",
    \( (*\ lz, z\ *) \), " "}]\)