用C語言編寫6次方程的通解程序？

這可用牛頓迭代法求解。

#include<stdio.h>

#include<math.h>

double

f(double

x)

/*函數*/

{

double

fx;

fx=cos(x)-x;

return

fx;

}

double

Df(double

x)

/*函數的導數*/

{

double

fx;

fx=-sin(x)-1;

return

fx;

}

main()

{

double

epsilon1,epsilon2,alpha;

int

N,n;

double

root;

double

x0,x1,F,DF,tol,k;

printf("請輸入初值alpha:");

scanf("%lf",&alpha);

printf("請輸入精度epsilon1:");

scanf("%lf",&epsilon1);

printf("請輸入精度epsilon2:");

scanf("%lf",&epsilon2);

printf("請輸入最大迭代次數N:");

scanf("%d",&N);

x0=alpha;

for(n=1;n<=N;n++)

{

F=f(x0);

DF=Df(x0);

if(abs(F-x0)<epsilon1)

{

printf("%lf",&x0);

goto

end;

}

else

if(abs(DF)<epsilon2)

{

printf("失??！");

goto

end;

}

else

{

x1==x0-F/DF;

tol=abs(x1-x0);

if(tol<epsilon1)

{

printf("%lf",&x1);

goto

end;

}

}

x0=x1;

k=k+1;

}

end:

printf("結束！");

}