diff --git a/logical_design/logical_design.ipynb b/logical_design/logical_design.ipynb
index 4b4d08f..66b9713 100644
--- a/logical_design/logical_design.ipynb
+++ b/logical_design/logical_design.ipynb
@@ -88,7 +88,7 @@
     "**NOR gates**:If a NOR gate has one (or two) external inputs leading into it, only one (or no) NOR gates can feed into it. \n",
     "\n",
     "\\begin{equation}\n",
-    "\\text{NOR}_{2} + \\text{NOR}_{3} + \\text{inputA}_{1} + \\text{inputB}_{2} \\leq 2\n",
+    "\\text{NOR}_{2} + \\text{NOR}_{3} + \\text{inputA}_{1} + \\text{inputB}_{1} \\leq 2\n",
     "\\end{equation}\n",
     "\n",
     "\\begin{equation}\n",