Changed the readme to reflect the changes I had made

Author: MatteoRaso

README.md

@@ -26,8 +26,14 @@ These repository is a collection of useful algorithms and data structures built
     * Palindrome
   * maths
     * to_polar
+  *arithmetic_analysis
+    * bisection
+    * newton
+    * secant
+    * false position
   * other
     * tic_tac_toe
+  
 
 * machine-learning
   * nearest neighbor