Решите уравнение 6(x+1)^2+2(x-1)(x^2+x+1)-2(x+1)^3=26

6*(x+1)^2+2*(x-1)*(x^2+x+1)-2*(x+1)^3 = 26;
6*(x^2+2*x+1)+2*(x^3+x^2+x-x^2-x-1)-2*(x^3+3*x^2+3*x+1) = 26;
6*x^2+12*x+6+2*(x^3-1)-2*x^3-6*x^2-6*x-2 = 26;
6*x^2+12*x+6+2*x^3-2-2*x^3-6*x^2-6*x-2 = 26;
6*x+2 = 26;
6*x = 26-2;
6*x = 24;
x = 24/6;
x = 4.
Ответ: X = 6.