Yeah, I'm done.
Mort and Rimp are right.
However, I couldn't solve its biquadratic equation. Maybe its solution will show that he is also right. But it seems I made a mistake somewhere, or the equation is incorrect, because I got some nonsense instead of a solution.
Знание некоторых закономерностей освобождает от изучения многих фактов.
Мечты сбываются рано или поздно, так или иначе.