#include<stdio.h> double a3,a2,a1,a0;//跨函数的变量弄成全局变量 double f(double x){ return a3*x*x*x+a2*x*x+a1*x+a0; } int main(){ double a,b,mid; //mid代表是根 scanf("%lf %lf %lf %lf",&a3,&a2,&a1,&a0); scanf("%lf %lf",&a,&b); while(f(a)...