diff --git a/units/en/unit4/pg-theorem.mdx b/units/en/unit4/pg-theorem.mdx
index ff619136..566d36cb 100644
--- a/units/en/unit4/pg-theorem.mdx
+++ b/units/en/unit4/pg-theorem.mdx
@@ -36,7 +36,7 @@ Thus we can rewrite the sum as
 
 We can then use the *derivative log trick* (also called *likelihood ratio trick* or *REINFORCE trick*), a simple rule in calculus that implies that \\( \nabla_x log f(x) = \frac{\nabla_x f(x)}{f(x)} \\)
 
-So given we have \\(\frac{\nabla_\theta P(\tau;\theta)}{P(\tau;\theta)} \\) we transform it as \\(\nabla_\theta log P(\tau|\theta) \\)
+So given we have \\(\frac{\nabla_\theta P(\tau;\theta)}{P(\tau;\theta)} \\) we transform it as \\(\nabla_\theta log P(\tau;\theta) \\)