diff --git a/poincare/include/poincare/trigonometry.h b/poincare/include/poincare/trigonometry.h
index 11553b48b..7f2f1b5e7 100644
--- a/poincare/include/poincare/trigonometry.h
+++ b/poincare/include/poincare/trigonometry.h
@@ -24,7 +24,6 @@ public:
   template <typename T> static std::complex<T> ConvertRadianToAngleUnit(const std::complex<T> c, Preferences::AngleUnit angleUnit);
   template <typename T> static std::complex<T> RoundToMeaningfulDigits(const std::complex<T> result, const std::complex<T> input);
 private:
-  static Expression mapIfPossible(Expression & e, ExpressionNode::ReductionContext reductionContext);
   template <typename T> static T RoundToMeaningfulDigits(T result, T input);
 };
 
diff --git a/poincare/src/trigonometry.cpp b/poincare/src/trigonometry.cpp
index a7963ed5d..294f84121 100644
--- a/poincare/src/trigonometry.cpp
+++ b/poincare/src/trigonometry.cpp
@@ -124,9 +124,8 @@ Expression Trigonometry::shallowReduceDirectFunction(Expression & e, ExpressionN
 
   // Step 0. Map on matrix child if possible
   {
-    Expression mapped = mapIfPossible(e, reductionContext);
-    if (!mapped.isUninitialized()) {
-      return mapped;
+    if (e.childAtIndex(0).type() == ExpressionNode::Type::Matrix) {
+      return e.mapOnMatrixFirstChild(reductionContext);
     }
   }
 
@@ -295,9 +294,8 @@ Expression Trigonometry::shallowReduceInverseFunction(Expression & e,  Expressio
   assert(isInverseTrigonometryFunction(e));
   // Step 0. Map on matrix child if possible
   {
-    Expression mapped = mapIfPossible(e, reductionContext);
-    if (!mapped.isUninitialized()) {
-      return mapped;
+    if (e.childAtIndex(0).type() == ExpressionNode::Type::Matrix) {
+      return e.mapOnMatrixFirstChild(reductionContext);
     }
   }
 
@@ -415,13 +413,6 @@ std::complex<T> Trigonometry::ConvertRadianToAngleUnit(const std::complex<T> c,
   return c;
 }
 
-Expression Trigonometry::mapIfPossible(Expression & e, ExpressionNode::ReductionContext reductionContext) {
-  if (e.childAtIndex(0).type() == ExpressionNode::Type::Matrix) {
-    return e.mapOnMatrixFirstChild(reductionContext);
-  }
-  return Expression();
-}
-
 template<typename T>
 T Trigonometry::RoundToMeaningfulDigits(T result, T input) {
   /* Cheat: openbsd trigonometric functions are numerical implementation and