import math

def quadratic_equation(a, b, c):

    t = math.sqrt(b * b - 4 * a *c)

    x1 = (-b + t)/2 * a

    x2 = (-b - t)/2 * a

    return x1, x2

print quadratic_equation(2, 3, 0)

print quadratic_equation(1, -6, 5)

我代码原来写是这样,结果不是理想中那样,后来改成

import math

def quadratic_equation(a, b, c):

    t = math.sqrt(b * b - 4 * a *c)

    x1 = (-b + t)/(2 * a)

    x2 = (-b - t)/(2 * a) 

    return x1, x2

print quadratic_equation(2, 3, 0)

print quadratic_equation(1, -6, 5)

就对了,就是把 2 * a 改成 (2 * a),为什么呢,运算的顺序不是一样的吗