\[\boxed{\text{658\ (658).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
Пояснение.
Решение.
\[\textbf{а)}\ a^{2} + a = a(a + 1)\]
\[\textbf{б)}\ x^{3} - x^{2} = x^{2}(x - 1)\]
\[\textbf{в)}\ c^{5} + c^{7} = c^{5}(1 + c^{2})\]
\[\textbf{г)}\ a^{3} - a^{7} = a^{3}(1 - a^{4})\]
\[\textbf{д)}\ 3m^{2} + 9m^{3} = 3m^{2}(1 + 3m)\]
\[\textbf{е)}\ 9p^{3} - 8p = p(9p^{2} - 8)\]
\[\textbf{ж)}\ 4c^{2} - 12c^{4} = 4c^{2}(1 - 3c^{2})\]
\[\textbf{з)}\ 5x^{5} - 15x^{3} = 5x^{3}(x^{2} - 3)\]
\[\textbf{и)} - 12y^{4} - 16y =\]
\[= - 4y \cdot (3y^{3} + 4)\]