#原函数换成题干的*********************
def fx(x):
    return x**4-3*x+1

# 二分法求解方程的根
def SolveByDivTwo(x1,x2,err):
    count = 1
    
    while abs(x2-x1) >= err:
        x = (x1+x2)/2
        print(f"k={count},a{count}={x1},b{count}={x2},x{count}={x},fx(x)={fx(x)}")
        if fx(x) * fx(x1) < 0:
            x2 = x
        else:
            x1 = x
        count += 1

    return (x1+x2)/2

#范围和精度要求换成题干的############
if __name__ == "__main__":
    x1 = 0.3
    x2 = 0.4
    err = 0.5e-5     #精度要求##################
    root = SolveByDivTwo(x1, x2, err)
    print(f"Root: {root:.5f}")