diff --git a/src/1_complex_numbers.md b/src/1_complex_numbers.md
index 68224c173795f27876fa8f60ebd5930e3fe63eb9..44598326e29bb1a10f15ee0e59a8b31818c2edd6 100644
--- a/src/1_complex_numbers.md
+++ b/src/1_complex_numbers.md
@@ -72,7 +72,7 @@ Check this!
 !!! check "Example:"
     $$\begin{align} 
     \frac{1 + 2{\rm i}}{1 - 2{\rm i}} &= \frac{(1 + 2{\rm i})(1 + 2{\rm i})}{1^2 + 2^2} = \frac{1+4{\rm i} -4}{5}\\
-    & = -\frac{3}{5} + {\rm i} \frac{8}{5}
+    & = -\frac{3}{5} + {\rm i} \frac{4}{5}
     \end{align}$$
 
 ### Visualization: the complex plane