diff --git a/backpropagation.qmd b/backpropagation.qmd
index 9831156..668a710 100644
--- a/backpropagation.qmd
+++ b/backpropagation.qmd
@@ -705,7 +705,7 @@ Let's compute the backward pass output: $$\begin{aligned}
     &= [\mathbf{g}_{\texttt{out}}^a, \mathbf{g}_{\texttt{out}}^b] \frac{\partial [\mathbf{x}_{\texttt{out}}^a, \mathbf{x}_{\texttt{out}}^b]}{\partial \mathbf{x}_{\texttt{in}}}\\
     &= [\mathbf{g}_{\texttt{out}}^a, \mathbf{g}_{\texttt{out}}^b] \frac{\partial [\mathbf{x}_{\texttt{in}}, \mathbf{x}_{\texttt{in}}]}{\partial \mathbf{x}_{\texttt{in}}}\\
     &= [\mathbf{g}_{\texttt{out}}^a, \mathbf{g}_{\texttt{out}}^b][1, 1]^\mathsf{T}\\
-    &= \mathbf{g}_{\texttt{out}}^b + \mathbf{g}_{\texttt{out}}^b
+    &= \mathbf{g}_{\texttt{out}}^a + \mathbf{g}_{\texttt{out}}^b
 \end{aligned}$$ So, branching just sums both the gradients passed
 backward to it.