WIP #931 use Simplify to create better L'Hospitale results

- set LIMIT_LHOSPITAL_RECURSION_LIMIT = 20 to avoid StackOverflow

Author: axkr

symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/basic/Config.java

@@ -309,7 +309,7 @@ public static Cache<IExpr, Object> getExprCache() {
   public static int INTEGRATE_RUBI_TIMELIMIT = 8;
 
   /** Define the recursion limit for <code>Limit#lHospitalesRule()</code> method. */
-  public static int LIMIT_LHOSPITAL_RECURSION_LIMIT = 128;
+  public static int LIMIT_LHOSPITAL_RECURSION_LIMIT = 20;
 
   /**
    * Flag for thread usage.

symja_android_library/matheclipse-core/src/main/java/org/matheclipse/core/builtin/SeriesFunctions.java

@@ -476,7 +476,7 @@ private static IExpr lHospitalesRule(IExpr numerator, IExpr denominator, LimitDa
               IExpr expr = engine.evalQuiet(F.Times(F.D(F.Power(numerator, exp), x),
                   F.Power(F.D(denominator.base(), x), F.CN1)));
               if (expr.isTimes() && expr.leafCount() < Config.MAX_SIMPLIFY_TOGETHER_LEAFCOUNT) {
-                expr = engine.evalQuiet(F.Expand(expr));
+                expr = engine.evalQuiet(F.Simplify(expr));
               }
               expr = evalLimit(expr, data, engine);
               if (expr.isNumber()) {
@@ -491,6 +491,9 @@ private static IExpr lHospitalesRule(IExpr numerator, IExpr denominator, LimitDa
         }
         IExpr expr =
             engine.evalQuiet(F.Times(F.D(numerator, x), F.Power(F.D(denominator, x), F.CN1)));
+        if (expr.isTimes() && expr.leafCount() < Config.MAX_SIMPLIFY_TOGETHER_LEAFCOUNT) {
+          expr = engine.evalQuiet(F.Simplify(expr));
+        }
         return evalLimit(expr, data, engine);
       } catch (RecursionLimitExceeded rle) {
         engine.setRecursionLimit(recursionLimit);