计算二元函数

一元二次函数的计算

#include<stdio.h><span style="white-space:pre"></span>//程序中要调用求平方根#include<math.h>#define EXP 0.00000000001<span style="white-space:pre"></span>//判断是否等于零int main() {double a;double b;double c;double disc;<span style="white-space:pre"></span>//disc是判别式sqrt(b*b-4*a*c)printf("请分别输入a,b,c的系数\n");<span style="white-space:pre"></span>scanf("%lf %lf %lf",&a,&b,&c);<span style="white-space:pre"></span>//输入双精度浮点型变量的值要用格式声明"%lf"disc = sqrt(b*b-4*a*c);if(a>= -EXP&&a<= EXP){//a=0时不是一元二次方程 printf("不是一元二次方程");}else{if((disc >= -EXP)&&(disc <= EXP)){//disc=0时 double x; printf("方程只有一个实数根：X=%lf",-(b)/(2*a));}if(disc>0.0){//disc>o时 double x1,x2;x1 = (-b+disc)/(2*a);x2 = (-b-disc)/(2*a);printf("x1 = %lf\nx2 = %lf",x1,x2);}if(disc<0.0){//disc<o时 printf("有两个共轭复数根"); }}return 0;}