use align environment, not aligned

aligned is only for when you are already inside a math environment (e.g. inside align)

examples/notebooks/Part 5 - Rich Display System.ipynb

@@ -1296,28 +1296,29 b''
      "collapsed": false,
      "input": [
       "%%latex\n",
-      "\\begin{aligned}\n",
+      "\\begin{align}\n",
       "\\nabla \\times \\vec{\\mathbf{B}} -\\, \\frac1c\\, \\frac{\\partial\\vec{\\mathbf{E}}}{\\partial t} & = \\frac{4\\pi}{c}\\vec{\\mathbf{j}} \\\\\n",
       "\\nabla \\cdot \\vec{\\mathbf{E}} & = 4 \\pi \\rho \\\\\n",
       "\\nabla \\times \\vec{\\mathbf{E}}\\, +\\, \\frac1c\\, \\frac{\\partial\\vec{\\mathbf{B}}}{\\partial t} & = \\vec{\\mathbf{0}} \\\\\n",
       "\\nabla \\cdot \\vec{\\mathbf{B}} & = 0\n",
-      "\\end{aligned}"
+      "\\end{align}"
      ],
      "language": "python",
      "metadata": {},
      "outputs": [
       {
        "latex": [
-        "\\begin{aligned}\n",
+        "\\begin{align}\n",
         "\\nabla \\times \\vec{\\mathbf{B}} -\\, \\frac1c\\, \\frac{\\partial\\vec{\\mathbf{E}}}{\\partial t} & = \\frac{4\\pi}{c}\\vec{\\mathbf{j}} \\\\\n",
         "\\nabla \\cdot \\vec{\\mathbf{E}} & = 4 \\pi \\rho \\\\\n",
         "\\nabla \\times \\vec{\\mathbf{E}}\\, +\\, \\frac1c\\, \\frac{\\partial\\vec{\\mathbf{B}}}{\\partial t} & = \\vec{\\mathbf{0}} \\\\\n",
         "\\nabla \\cdot \\vec{\\mathbf{B}} & = 0\n",
-        "\\end{aligned}"
+        "\\end{align}"
        ],
+       "metadata": {},
        "output_type": "display_data",
        "text": [
-        "<IPython.core.display.Latex at 0x10a617c90>"
+        "<IPython.core.display.Latex at 0x106c04dd0>"
        ]
       }
      ],

examples/notebooks/Typesetting Math Using MathJax.ipynb

@@ -1,6 +1,6 b''
 {
  "metadata": {
-  "name": "Typesetting Math Using MathJax"
+  "name": ""
  },
  "nbformat": 3,
  "nbformat_minor": 0,
@@ -24,18 +24,18 b''
       "\n",
       "## The Lorenz Equations\n",
       "### Source\n",
-      "```\\begin{aligned}\n",
+      "```\\begin{align}\n",
       "\\dot{x} & = \\sigma(y-x) \\\\\n",
       "\\dot{y} & = \\rho x - y - xz \\\\\n",
       "\\dot{z} & = -\\beta z + xy\n",
-      "\\end{aligned}\n",
+      "\\end{align}\n",
       "```\n",
       "### Display\n",
-      "\\begin{aligned}\n",
+      "\\begin{align}\n",
       "\\dot{x} & = \\sigma(y-x) \\\\\n",
       "\\dot{y} & = \\rho x - y - xz \\\\\n",
       "\\dot{z} & = -\\beta z + xy\n",
-      "\\end{aligned}"
+      "\\end{align}"
      ]
     },
     {
@@ -140,18 +140,18 b''
      "source": [
       "## Maxwell's Equations\n",
       "### Source\n",
-      "```\\begin{aligned}\n",
+      "```\\begin{align}\n",
       "\\nabla \\times \\vec{\\mathbf{B}} -\\, \\frac1c\\, \\frac{\\partial\\vec{\\mathbf{E}}}{\\partial t} & = \\frac{4\\pi}{c}\\vec{\\mathbf{j}} \\\\   \\nabla \\cdot \\vec{\\mathbf{E}} & = 4 \\pi \\rho \\\\\n",
       "\\nabla \\times \\vec{\\mathbf{E}}\\, +\\, \\frac1c\\, \\frac{\\partial\\vec{\\mathbf{B}}}{\\partial t} & = \\vec{\\mathbf{0}} \\\\\n",
       "\\nabla \\cdot \\vec{\\mathbf{B}} & = 0 \n",
-      "\\end{aligned}\n",
+      "\\end{align}\n",
       "```\n",
       "### Display\n",
-      "\\begin{aligned}\n",
+      "\\begin{align}\n",
       "\\nabla \\times \\vec{\\mathbf{B}} -\\, \\frac1c\\, \\frac{\\partial\\vec{\\mathbf{E}}}{\\partial t} & = \\frac{4\\pi}{c}\\vec{\\mathbf{j}} \\\\   \\nabla \\cdot \\vec{\\mathbf{E}} & = 4 \\pi \\rho \\\\\n",
       "\\nabla \\times \\vec{\\mathbf{E}}\\, +\\, \\frac1c\\, \\frac{\\partial\\vec{\\mathbf{B}}}{\\partial t} & = \\vec{\\mathbf{0}} \\\\\n",
       "\\nabla \\cdot \\vec{\\mathbf{B}} & = 0 \n",
-      "\\end{aligned}"
+      "\\end{align}"
      ]
     },
     {