Question

用二分法求方程x^5+3x-1=0的最小正根,要求误差不小于0.000005

Answer 1

x^5+3x-1=0 （C语言源码）：

/* Begin */

#include <stdio.h>
#include <math.h>

#define EXPR pow(x,5)+3*x-1

float Solve(float a,float b,float Err)
{
float x = a;
float f1,f2;

while((b - a) > Err)
{
f1 = EXPR;
x = (a + b) / 2;
f2 = EXPR;

if(f1 * f2 < 0)
{
b = x;
x = a;
}
else
{
a = x;
}
}

return x;
}

int main()
{
float ans;
ans = Solve(0,0.5,0.000005);
printf("%f",ans);
return 0;
}

/* End */

Answer 2

一楼霸气