import work from sqrt on smpl for absPoly and this_append_before

pymath/calculus/abstract_polynom.py

@@ -385,6 +385,8 @@ class AbstractPolynom(Explicable):
 
     def simplify(self):
         """Same as reduce """
+        if isNumber(self._letter):
+            return self.replace_letter(self._letter).simplify()
         return self.reduce()
 
     @classmethod

pymath/calculus/explicable.py

@@ -124,7 +124,7 @@ class Explicable(Renderable):
         >>> print(e.steps)
         ['cook', 'eat', 'sleep']
         """
-        self.steps = steps + self.steps
+        self.steps = list(steps) + self.steps
 
     def steal_history(self, arg1):
         """ Steal the history of arg1 for itself