c语言如何实现二次函数,c语言如何调用两次函数

C语言写二次函数

首先你已经很清楚的说明了你这个程序是用C语言写二次函数的，而当a=0时，就不是二次函数了，应该按照一次函数来进行计算，否则 一个数除以0就没有意义了.~

#include stdio.h

#include stdlib.h

#include math.h

int main()

{

float a,b,c;

float x1,x2,m;

printf("input number a=:");

scanf("%f",a);

printf("input number b=:");

scanf("%f",b);

printf("input number c=:");

scanf("%f",c);

if(a==0)

printf("一根:%f\n",c*(-1)/b);

else if(a==0b==0)

printf("无意义！");

else

{

m=b*b-4*a*c;

if(m0)

{

printf("两根\n");

printf("x1=%f\n",(-b+sqrt(m))/(2*a));

printf("x2=%f\n",(-b-sqrt(m))/(2*a));

}

else if(m==0)

printf("x1=x2=%f\n",x1);

}

else

printf("无实根\n");

}

return 0;

}

C语言怎样设计二次函数，请各位哥哥姐姐帮帮忙，

#include stdio.h

#include stdlib.h

#include math.h

int main()

{

float a,b,c;

float x1,x2,m;

printf("input number a=:");

scanf("%f",a);

printf("input number b=:");

scanf("%f",b);

printf("input number c=:");

scanf("%f",c);

m=b*b-4*a*c;

if(m=0a！=0){

if(m0){

x1=(-b+sqrt(m))/(2*a);

x2=(-b-sqrt(m))/(2*a);

printf("两根\n");

printf("x1=%f\n",x1);

printf("x2=%f\n",x2);}

else

printf("一根\n");

printf("x1=x2=%f\n",x1);}

else

{

if(a=0 b!=0) printf("根是x=-c/b");

if(a=0b=0) printf("为常函数")；

if(a!=0) printf("无根\n");

}

system("PAUSE");

return 0; }

c语言解答二次函数

这个简单啊

#includestdio.h

#includemath.h

main()

{

double a,b,c,w;

printf("请输入三个数（方程的系数），中间用空格分开\n");

scanf("%lf%lf%lf",a,b,c);

w=b*b-4*a*c;

if (w0)printf("方程无解\n");

else if(w==0)printf("方程有一个解：x=%lf\n",-b/(2*a));

else printf("方程有两个解：x1=%lf,x2=%lf\n",(-b+sqrt(w))/(2*a),(-b-sqrt(w))/(2*a));

}

用c语言画一个2次函数图像

#include windows.h

LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,

PSTR szCmdLine, int iCmdShow)

{

static TCHAR szAppName[]=TEXT("二次函数");

HWND         hwnd;

MSG          msg;

WNDCLASS     wndclass;

wndclass.style=CS_HREDRAW|CS_VREDRAW;

wndclass.lpfnWndProc=WndProc;

wndclass.cbClsExtra=0;

wndclass.cbWndExtra=0;

wndclass.hInstance=hInstance;

wndclass.hIcon=LoadIcon(NULL, IDI_APPLICATION);

wndclass.hCursor=LoadCursor(NULL, IDC_ARROW);

wndclass.hbrBackground=(HBRUSH)GetStockObject(WHITE_BRUSH);

wndclass.lpszMenuName=NULL;

wndclass.lpszClassName=szAppName;

if (!RegisterClass(wndclass))

{

MessageBox(NULL, TEXT("Error"),

szAppName, MB_ICONERROR);

return 0;

}

hwnd=CreateWindow(szAppName, TEXT("二次函数"),

WS_OVERLAPPEDWINDOW,

CW_USEDEFAULT, CW_USEDEFAULT,

CW_USEDEFAULT, CW_USEDEFAULT,

NULL, NULL, hInstance, NULL);

ShowWindow(hwnd, iCmdShow);

UpdateWindow(hwnd);

while (GetMessage(msg, NULL, 0, 0))

{

TranslateMessage(msg);

DispatchMessage(msg);

}

return msg.wParam;

}

LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)

{

static int  cxClient, cyClient;

const static int n=1000;

HDC         hdc;

int         i;

PAINTSTRUCT ps;

POINT       apt[n];

switch (message)

{

case WM_SIZE:

cxClient=LOWORD(lParam);

cyClient=HIWORD(lParam);

return 0;

case WM_PAINT:

hdc=BeginPaint(hwnd, ps);

MoveToEx(hdc, 0, cyClient/2, NULL);

LineTo(hdc, cxClient, cyClient/2);

MoveToEx(hdc, cxClient/2, 0, NULL);

LineTo(hdc, cxClient/2, cyClient);

for (i=0; i  n;++i)

{

apt[i].x=cxClient/4+i; apt[i].y=cyClient-(cyClient/2-i)*(cyClient/2-i)/300-cyClient/2+100;

}

Polyline(hdc, apt, n);

return 0;

case WM_DESTROY:

PostQuitMessage(0);

return 0;

}

return DefWindowProc(hwnd, message, wParam, lParam);

}