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我想解决一个二次方程。我有所有类型为double的变量,以及变量Nan的结果。为什么双型变量返回Nan?
double a, b, c, x1, d, x2, s ;
Console.WriteLine("Enter a value a: ");
a = double.Parse(Console.ReadLine());
Console.WriteLine("Enter a value b: ");
b = double.Parse(Console.ReadLine());
Console.WriteLine("Enter a value c: ");
c = double.Parse(Console.ReadLine());
d = b * b - 4 * a * c;
Console.WriteLine("solution: ");
Console.WriteLine("1) Substitute the values entered in the equation " + "{0} * x^2 + {1} * x + {2} = 0 ", a, b, c);
Console.WriteLine("2) Сalculate the discriminant: d = b * b - 4 * a * c ");
Console.WriteLine("3) D = {0}*{0} - 4*{1}*{2} = {3}", b, a, c, d);
if (d > 0)
{
x1 = (-b + Math.Sqrt(d))/2*a;
x2 = (-b - Math.Sqrt(d))/2*a;
s = (a * Math.Sqrt(x2))+ (b * x1) + c;
Console.WriteLine("{0} ; {1}",x1,x2);
Console.WriteLine("Сheck: " + "{0} * {1} + {2} * {3} + {4} = {5} ", a, x2, b, x1, c, s);
}
else if (d == 0)
{
x1 = (-b)/2*a;
Console.WriteLine(x1);
}
else if (d < 0)
{
Console.WriteLine("Since the discriminant is less than zero, then the equation has no solution.");
}
以下字符串返回南s =(a * Math.Sqrt(x2))+(b * x1)+ c; 为什么是南而不是双?