XXX fix expansion for f0 in (S.Zero, S.Infinity, S.NegativeInfinity)

diofant · Dec 6, 2015 · 776b71d · 776b71d
1 parent 6749a87
commit 776b71d
Showing 1 changed file with 4 additions and 2 deletions.
diff --git a/sympy/core/power.py b/sympy/core/power.py
@@ -1265,9 +1265,11 @@ def _taylor(expr, x, n):
         f0 = b.limit(x, 0)
         a = e
 
-        if f0 is S.Zero:
+        if f0 in (S.Zero, S.Infinity, S.NegativeInfinity):
             lt = b.as_leading_term(x)
-            return lt**a*((b/lt)*a)._eval_nseries(x, n, logx)
+            if f0 == S.NegativeInfinity:
+                lt = -lt
+            return (lt**a*((b/lt).expand(mul=True)**a)._eval_nseries(x, n, logx)).expand(mul=True)
 
         from sympy.functions.combinatorial.factorials import factorial, binomial
         from sympy.functions.elementary.complexes import arg