diff --git a/module3/exo3/exercice.ipynb b/module3/exo3/exercice.ipynb
index e355021070b94253d71d85abf1f655b07fe82b1d..c0873337b5932c69c2494b38a6f007c1ef3c5a8d 100644
--- a/module3/exo3/exercice.ipynb
+++ b/module3/exo3/exercice.ipynb
@@ -733,10 +733,42 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 33,
    "metadata": {},
    "outputs": [],
-   "source": []
+   "source": [
+    "# Import des librairies\n",
+    "import scipy.fftpack"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 44,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "yf = pd.Series(scipy.fftpack.fft(data['untrend_data']))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 45,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "dtype('complex128')"
+      ]
+     },
+     "execution_count": 45,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "yf.dtype"
+   ]
   },
   {
    "cell_type": "code",