Fix typo in partial differentiation equation

Author: arm61

differentiation/partial.ipynb

@@ -100,7 +100,7 @@
     "\n",
     "$$\n",
     "\\begin{aligned}\n",
-    "\\left(\\frac{\\partial y}{\\partial x}\\right)_z & = \\frac{\\partial}{\\partial x} 2\\ln(z) + \\frac{partial}{\\partial x} \\sin(zx) \\\\ \n",
+    "\\left(\\frac{\\partial y}{\\partial x}\\right)_z & = \\frac{\\partial}{\\partial x} 2\\ln(z) + \\frac{\\partial}{\\partial x} \\sin(zx) \\\\ \n",
     " & = 0 + z\\cos(zx) = z\\cos(zx)\n",
     "\\end{aligned}\n",
     "$$\n",