a) (a + 1)(a + 1)(a + 1);
б) (a + b)(a - b)(a + b);
в) (a + b + c)(a + 1);
г) (x + 1)(x2 - x + 1);
д ) (x3 + 2x - 3)(2 – 3x);
е ) (a + b + c)(a + b - c);​