复杂方程可以自己定义，以下是看别人的题目，然后自己来做

以下是计算结果

private void GetMinResult(out double resultX1, out double min){double x1, result;Random random1 = new Random(DateTime.Now.Millisecond* DateTime.Now.Second);min = 999999;resultX1 = 0;for (int i = 0; i < 654321; i++){if (random1.Next(0, 100) % 2 == 0){x1 = resultX1 + random1.NextDouble()*100;}else{x1 = resultX1 - random1.NextDouble()*100;}if (x1 < 0 || x1 > 50){continue;}result = x1 * Math.Sin(x1) * Math.Cos(2 * x1) - 2 * x1 * Math.Sin(3 * x1) + 3 * x1 * Math.Sin(4 * x1);if (result < min){resultX1 = x1;min = result;}}}