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double f(double u) {
return sqrt(2*u)+2*u-6.3;
}
 
void __fastcall TForm1::Button4Click(TObject *Sender)
{
float l,r,h,dh;
l=StrToFloat(Edit1->Text);
r=StrToFloat(Edit2->Text);
h=l;
dh=(r-l)/30;
 while (h<r)
     {
         Series1->AddXY(h,f(h));
       h=h+dh;
     }
}

//---------------------------------------------------------------------------
 
#include <vcl.h>
#include <math.h>
#pragma hdrstop
 
#include "Unit1.h"
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
int i;
double l, r, Znf[30], shag, h, s;
double f(double u)
{
  return sin(u);
}
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
}
//---------------------------------------------------------------------------
 
 
void __fastcall TForm1::BitBtn1Click(TObject *Sender)
{
  l=StrToFloat(Edit1->Text);
  r=StrToFloat(Edit2->Text);
  shag=(r-l)/30;
  h=l;
  for (i=0; i<30; i++)
  {
    Znf[i]=f(h);
    Series1->Add(Znf[i], h, clRed);
    h=h+shag;
  }
 
}
//---------------------------------------------------------------------------
 
void __fastcall TForm1::Button1Click(TObject *Sender)
{
  l=StrToFloat(Edit1->Text);
  r=StrToFloat(Edit2->Text);
  shag=(r-l)/30;
  h=l;
  Timer1->Enabled=true;
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Timer1Timer(TObject *Sender)
{
  s=f(h);
  Series1->Add(s,h, clRed);
  h=h+shag;
  if (h>=r) Timer1->Enabled=false;
}
//---------------------------------------------------------------------------