public void FindNthRoot_Exception(double number, int n, double accuracy, double expectedResult) =>
 Assert.Throws <ArgumentOutOfRangeException>(() => FindNthRoots.FindNthRoot(number, n, accuracy));
 public static void FindNthRoot(double number, int n, double accuracy, double expectedResult)
 {
     Assert.AreEqual(FindNthRoots.FindNthRoot(number, n, accuracy), expectedResult, accuracy);
 }