# _*_ coding utf-8 _*_

import math

def quadratic(a,b,c):

    for i in [a,b,c]:

        if not isinstance(i,int):

            raise TypeError('bad operant type')

    if a == 0:

        raise TypeError('bad operant type')

    delta = b**2 - 4 * a * c

    if delta < 0:

        return "无实数根"

    x1 = (-b + math.sqrt(delta)) / (2 * a)

    x2 = (-b - math.sqrt(delta)) / (2 * a)

    return x1, x2