При каких значениях параметра a уравнение ax^2 - 2x -3a=0 связаны

   По аксиоме Виета имеем:

   ax^2 - 2x - 3a = 0;

• x1 + x2 = 2/a;
  x1 * x2 = -3;
  x1 + 2x2 = 1;
• 1 - 2x2 + x2 = 2/a;
  (1 - 2x2) * x2 = -3;
  x1 = 1 - 2x2;
• 1 - x2 = 2/a;
  x2 - 2x2^2 + 3 = 0;
  x1 = 1 - 2x2;
• a = 2/(1 - x2);
  2x2^2 - x2 - 3 = 0;
  x1 = 1 - 2x2;

• 2x2^2 - x2 - 3 = 0;
• D = 1 + 4 * 2 * 3 = 25;
• x2 = (1 25)/4 = (1 5)/4;

   1) x2 = (1 - 5)/4 = -4/4 = -1;

• x1 = 1 - 2x2 = 1 - 2 * (-1) = 3;
• a = 2/(1 - x2) = 2/(1 + 1) = 1;

   2) x2 = (1 + 5)/4 = 6/4 = 3/2;

• x1 = 1 - 2x2 = 1 - 2 * 3/2 = -2;
• a = 2/(1 - 3/2) = 2/(-1/2) = -4.

   Ответ: -4 и 1.