diff --git a/content/CSE510/CSE510_L5.md b/content/CSE510/CSE510_L5.md
index d651270..ec59088 100644
--- a/content/CSE510/CSE510_L5.md
+++ b/content/CSE510/CSE510_L5.md
@@ -158,6 +158,7 @@ $$
 &= \frac{1}{n}\sum_{i=1}^{n} x_i + \frac{1}{n+1} x_{n}-\frac{1}{n}\hat{X}_n\\
 &= \hat{x}_{n} +\frac{1}{n+1} \left[x_{n+1} +\sum_{i=1}^{n} x_i-\frac{n+1}{n}\sum_{i=1}^{n} x_i\right]\\
 &= \hat{x}_{n} + \frac{1}{n+1} (x_{n+1} - \hat{X}_n)
+\end{aligned}
 $$
 
 ### Summary of passive RL