diff --git a/lectures/07_order_notation_recursion/README.md b/lectures/07_order_notation_recursion/README.md
index d026d16..11a0e6d 100644
--- a/lectures/07_order_notation_recursion/README.md
+++ b/lectures/07_order_notation_recursion/README.md
@@ -263,16 +263,12 @@ of the vector in reverse order?
 ## 7.17 Fibonacci Optimization: Order Notation of Time vs. Space
 
 The Fibonacci sequence is defined:
-$$
-F(n) = \begin{cases}
-0 & \text{if } n = 0 \\
-1 & \text{if } n = 1 \\
-F(n-1) + F(n-2) & \text{otherwise}
-\end{cases}
-$$
+![alt text](fibonacci_sequence.png "fibonacci sequence")
 
 1. Write a simple recursive version of Fibonacci that is a direct translation of the mathematical definition of the
 Fibonacci sequence.  
 2. Write an iterative version of Fibonacci that uses a vector to improve the running time of the function.  
 3. What is the order notation of the running time for each version?  
+- Play this [animation](https://jidongxiao.github.io/CSCI1200-DataStructures/animations/dynamic_memory/example1/index.html), which illustrates the time complexity of the recursvie version.
+
 4. What is the order notation of the memory usage for each version?