Update mathematics.py

Chapter_1/mathematics.py

@@ -5,7 +5,4 @@ print("sin(pi/2)  = {0}".format(math.sin(math.pi/2)))
 print("racine (9) = {0}".format(math.sqrt(9)))
 print("e^2        = {0}".format(math.exp(2)))
 print("Plus d'exemples ici :")
-print("http://www.cplusplus.com/reference/cmath/")
-
-
-
+print("https://docs.python.org/3.7/library/math.html")