答案:答:程序参见文件Cprogram\xt5_4_08.c#include "stdio.h"#include "math.h"main(){float a,b,c,fa,fb,fc;do{printf("Enter a,b:");scanf("%f,%f",&a,&b);fa=2*a*a*a-3*a*a 7*a-13;fb=2*b*b*b-3*b*b 7*b-13;}while(fa*fb>0);do{c=(a*fb-b*fa)/(fb-fa);fc=2*c*c*c-3*c*c 7*c-13;if(fa*fc>0){a=c;fa=fc;}else{b=c;fb=fc;}}while(fabs(fc)>0.0001);printf("x=%f,y=%f\n",c,fc);}