diff --git a/chapter_linear-networks/softmax-regression-scratch.md b/chapter_linear-networks/softmax-regression-scratch.md
index daa33345f..9eb8c1afe 100644
--- a/chapter_linear-networks/softmax-regression-scratch.md
+++ b/chapter_linear-networks/softmax-regression-scratch.md
@@ -130,7 +130,7 @@ d2l.reduce_sum(X, 0, keepdims=True), d2l.reduce_sum(X, 1, keepdims=True)
 
 (**
 $$
-\mathrm{softmax}(\mathbf{X})_{ij} = \frac{\exp(\mathbf{X}_{ij})}{\sum_k \exp(\mathbf{X}_{ik})}.
+\mathrm{softmax}(\mathbf{X_{ij}}) = \frac{\exp(\mathbf{X}_{ij})}{\sum_k \exp(\mathbf{X}_{ik})}.
 $$
 **)