diff --git a/module2/exo1/toy_notebook_en.ipynb b/module2/exo1/toy_notebook_en.ipynb
index 33e47b8676d503901d539bd17a8298335be5c013..5f23869f696b4c12ddda46cce90ee0652f57b07b 100644
--- a/module2/exo1/toy_notebook_en.ipynb
+++ b/module2/exo1/toy_notebook_en.ipynb
@@ -4,11 +4,11 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "# On the computation of $\\pi$\n",
+    "# On the computation of $\\\\pi$\n",
     "\n",
     "## Asking the maths library\n",
     "\n",
-    "My computer tells me that $\\pi$ is *approximatively*"
+    "My computer tells me that $\\\\pi$ is *approximatively*"
    ]
   },
   {