diff --git a/apps/graph/graph/extremum_graph_controller.cpp b/apps/graph/graph/extremum_graph_controller.cpp
index cf3971b69..aa84d7e1f 100644
--- a/apps/graph/graph/extremum_graph_controller.cpp
+++ b/apps/graph/graph/extremum_graph_controller.cpp
@@ -1,7 +1,7 @@
 #include "extremum_graph_controller.h"
-#include "../app.h"
+#include "../../shared/poincare_helpers.h"
+#include <poincare/serialization_helper.h>
 
-using namespace Shared;
 using namespace Poincare;
 
 namespace Graph {
@@ -16,7 +16,11 @@ const char * MinimumGraphController::title() {
 }
 
 Coordinate2D MinimumGraphController::computeNewPointOfInterest(double start, double step, double max, Poincare::Context * context) {
-  return functionStore()->modelForRecord(m_record)->nextMinimumFrom(start, step, max, context);
+  // TODO The following three lines should be factored.
+  constexpr int bufferSize = CodePoint::MaxCodePointCharLength + 1;
+  char unknownX[bufferSize];
+  Poincare::SerializationHelper::CodePoint(unknownX, bufferSize, UCodePointUnknownX);
+  return Shared::PoincareHelpers::NextMinimum(functionStore()->modelForRecord(m_record)->expressionReduced(context), unknownX, start, step, max, context);
 }
 
 MaximumGraphController::MaximumGraphController(Responder * parentResponder, GraphView * graphView, BannerView * bannerView, Shared::InteractiveCurveViewRange * curveViewRange, Shared::CurveViewCursor * cursor) :
@@ -29,7 +33,11 @@ const char * MaximumGraphController::title() {
 }
 
 Coordinate2D MaximumGraphController::computeNewPointOfInterest(double start, double step, double max, Poincare::Context * context) {
-  return functionStore()->modelForRecord(m_record)->nextMaximumFrom(start, step, max, context);
+  // TODO The following three lines should be factored.
+  constexpr int bufferSize = CodePoint::MaxCodePointCharLength + 1;
+  char unknownX[bufferSize];
+  Poincare::SerializationHelper::CodePoint(unknownX, bufferSize, UCodePointUnknownX);
+  return Shared::PoincareHelpers::NextMaximum(functionStore()->modelForRecord(m_record)->expressionReduced(context), unknownX, start, step, max, context);
 }
 
 }
diff --git a/apps/graph/graph/intersection_graph_controller.cpp b/apps/graph/graph/intersection_graph_controller.cpp
index 87f363fb7..8ef991990 100644
--- a/apps/graph/graph/intersection_graph_controller.cpp
+++ b/apps/graph/graph/intersection_graph_controller.cpp
@@ -1,7 +1,7 @@
 #include "intersection_graph_controller.h"
-#include "../app.h"
 #include "../../shared/poincare_helpers.h"
 #include <poincare/preferences.h>
+#include <poincare/serialization_helper.h>
 
 using namespace Shared;
 
@@ -41,12 +41,16 @@ void IntersectionGraphController::reloadBannerView() {
 }
 
 Poincare::Coordinate2D IntersectionGraphController::computeNewPointOfInterest(double start, double step, double max, Poincare::Context * context) {
+  // TODO The following three lines should be factored.
+  constexpr int bufferSize = CodePoint::MaxCodePointCharLength + 1;
+  char unknownX[bufferSize];
+  Poincare::SerializationHelper::CodePoint(unknownX, bufferSize, UCodePointUnknownX);
   Poincare::Coordinate2D result = Poincare::Coordinate2D(NAN, NAN);
   for (int i = 0; i < functionStore()->numberOfActiveFunctions(); i++) {
     Ion::Storage::Record record = functionStore()->activeRecordAtIndex(i);
     if (record != m_record) {
       Poincare::Expression e = functionStore()->modelForRecord(record)->expressionReduced(context);
-      Poincare::Coordinate2D intersection = functionStore()->modelForRecord(m_record)->nextIntersectionFrom(start, step, max, context, e);
+      Poincare::Coordinate2D intersection = Shared::PoincareHelpers::NextIntersection(functionStore()->modelForRecord(m_record)->expressionReduced(context), unknownX, start, step, max, context, e);
       if ((std::isnan(result.abscissa()) || std::fabs(intersection.abscissa()-start) < std::fabs(result.abscissa()-start)) && !std::isnan(intersection.abscissa())) {
         m_intersectedRecord = record;
         result = (std::isnan(result.abscissa()) || std::fabs(intersection.abscissa()-start) < std::fabs(result.abscissa()-start)) ? intersection : result;
diff --git a/apps/graph/graph/preimage_graph_controller.cpp b/apps/graph/graph/preimage_graph_controller.cpp
index 868b427b5..bf0785328 100644
--- a/apps/graph/graph/preimage_graph_controller.cpp
+++ b/apps/graph/graph/preimage_graph_controller.cpp
@@ -1,4 +1,6 @@
 #include "preimage_graph_controller.h"
+#include "../../shared/poincare_helpers.h"
+#include <poincare/serialization_helper.h>
 
 namespace Graph {
 
@@ -22,8 +24,12 @@ PreimageGraphController::PreimageGraphController(
 }
 
 Poincare::Coordinate2D PreimageGraphController::computeNewPointOfInterest(double start, double step, double max, Poincare::Context * context) {
+  // TODO The following three lines should be factored.
+  constexpr int bufferSize = CodePoint::MaxCodePointCharLength + 1;
+  char unknownX[bufferSize];
+  Poincare::SerializationHelper::CodePoint(unknownX, bufferSize, UCodePointUnknownX);
   Poincare::Expression expression = Poincare::Float<double>::Builder(m_image);
-  return functionStore()->modelForRecord(m_record)->nextIntersectionFrom(start, step, max, context, expression);
+  return Shared::PoincareHelpers::NextIntersection(functionStore()->modelForRecord(m_record)->expressionReduced(context), unknownX, start, step, max, context, expression);
 }
 
 }
diff --git a/apps/graph/graph/root_graph_controller.cpp b/apps/graph/graph/root_graph_controller.cpp
index 741a72961..e4062447a 100644
--- a/apps/graph/graph/root_graph_controller.cpp
+++ b/apps/graph/graph/root_graph_controller.cpp
@@ -1,5 +1,6 @@
 #include "root_graph_controller.h"
-#include "../app.h"
+#include "../../shared/poincare_helpers.h"
+#include <poincare/serialization_helper.h>
 
 using namespace Shared;
 using namespace Poincare;
@@ -16,7 +17,11 @@ const char * RootGraphController::title() {
 }
 
 Coordinate2D RootGraphController::computeNewPointOfInterest(double start, double step, double max, Context * context) {
-  return Coordinate2D(functionStore()->modelForRecord(m_record)->nextRootFrom(start, step, max, context), 0.0);
+  // TODO The following three lines should be factored.
+  constexpr int bufferSize = CodePoint::MaxCodePointCharLength + 1;
+  char unknownX[bufferSize];
+  Poincare::SerializationHelper::CodePoint(unknownX, bufferSize, UCodePointUnknownX);
+  return Coordinate2D(Shared::PoincareHelpers::NextRoot(functionStore()->modelForRecord(m_record)->expressionReduced(context), unknownX, start, step, max, context), 0.0);
 }
 
 }
diff --git a/apps/shared/cartesian_function.cpp b/apps/shared/cartesian_function.cpp
index a85bc818d..8e27cdb9e 100644
--- a/apps/shared/cartesian_function.cpp
+++ b/apps/shared/cartesian_function.cpp
@@ -104,34 +104,6 @@ double CartesianFunction::sumBetweenBounds(double start, double end, Poincare::C
   return PoincareHelpers::ApproximateToScalar<double>(integral, context);
 }
 
-Coordinate2D CartesianFunction::nextMinimumFrom(double start, double step, double max, Context * context) const {
-  constexpr int bufferSize = CodePoint::MaxCodePointCharLength + 1;
-  char unknownX[bufferSize];
-  SerializationHelper::CodePoint(unknownX, bufferSize, UCodePointUnknownX);
-  return PoincareHelpers::NextMinimum(expressionReduced(context), unknownX, start, step, max, context);
-}
-
-Coordinate2D CartesianFunction::nextMaximumFrom(double start, double step, double max, Context * context) const {
-  constexpr int bufferSize = CodePoint::MaxCodePointCharLength + 1;
-  char unknownX[bufferSize];
-  SerializationHelper::CodePoint(unknownX, bufferSize, UCodePointUnknownX);
-  return PoincareHelpers::NextMaximum(expressionReduced(context), unknownX, start, step, max, context);
-}
-
-double CartesianFunction::nextRootFrom(double start, double step, double max, Context * context) const {
-  constexpr int bufferSize = CodePoint::MaxCodePointCharLength + 1;
-  char unknownX[bufferSize];
-  SerializationHelper::CodePoint(unknownX, bufferSize, UCodePointUnknownX);
-  return PoincareHelpers::NextRoot(expressionReduced(context), unknownX, start, step, max, context);
-}
-
-Coordinate2D CartesianFunction::nextIntersectionFrom(double start, double step, double max, Poincare::Context * context, Expression e) const {
-  constexpr int bufferSize = CodePoint::MaxCodePointCharLength + 1;
-  char unknownX[bufferSize];
-  SerializationHelper::CodePoint(unknownX, bufferSize, UCodePointUnknownX);
-  return PoincareHelpers::NextIntersection(expressionReduced(context), unknownX, start, step, max, context, e);
-}
-
 void * CartesianFunction::Model::expressionAddress(const Ion::Storage::Record * record) const {
   return (char *)record->value().buffer+sizeof(CartesianFunctionRecordDataBuffer);
 }
diff --git a/apps/shared/cartesian_function.h b/apps/shared/cartesian_function.h
index a671667f4..d45d54f64 100644
--- a/apps/shared/cartesian_function.h
+++ b/apps/shared/cartesian_function.h
@@ -30,12 +30,6 @@ public:
   double approximateDerivative(double x, Poincare::Context * context) const;
   // Integral
   double sumBetweenBounds(double start, double end, Poincare::Context * context) const override;
-  // Extremum
-  Poincare::Coordinate2D nextMinimumFrom(double start, double step, double max, Poincare::Context * context) const;
-  Poincare::Coordinate2D nextMaximumFrom(double start, double step, double max, Poincare::Context * context) const;
-  // Roots
-  double nextRootFrom(double start, double step, double max, Poincare::Context * context) const;
-  Poincare::Coordinate2D nextIntersectionFrom(double start, double step, double max, Poincare::Context * context, Poincare::Expression expression) const;
 private:
   /* CartesianFunctionRecordDataBuffer is the layout of the data buffer of Record
    * representing a CartesianFunction. See comment on