diff --git a/11-Extended-Kalman-Filters.ipynb b/11-Extended-Kalman-Filters.ipynb
index e70d363..6082f0c 100644
--- a/11-Extended-Kalman-Filters.ipynb
+++ b/11-Extended-Kalman-Filters.ipynb
@@ -950,7 +950,7 @@
     "\n",
     "We model our system as a nonlinear motion model plus noise.\n",
     "\n",
-    "$$\\bar x = x + f(x, u) + \\mathcal{N}(0, Q)$$\n",
+    "$$\\bar x = f(x, u) + \\mathcal{N}(0, Q)$$\n",
     "\n",
     "\n",
     "\n",