diff --git a/src/8_differential_equations_2.md b/src/8_differential_equations_2.md
index 05dcf0b6742dea4baa97839c4f0d271a756be755..4afb3faa5fdeedd90f1cc6c4f14673493d4e2db3 100644
--- a/src/8_differential_equations_2.md
+++ b/src/8_differential_equations_2.md
@@ -587,5 +587,5 @@ necessary to work with numerical methods of solution.
 
     (a) $L = A(x) \frac{d^2 f}{dx^2}$
 
-    (b) $Lf = \frac{d}{dx} \big{()} A(x) \frac{df}{dx} \big{)}$
+    (b) $L = \frac{d}{dx} \big{(} A(x) \frac{df}{dx} \big{)}$