вправа 581 гдз 7 клас алгебра Мерзляк Полонський

Відповідь:

1) 6(1 - 2с)² = 6(1 - 4c + 4c²) =
= 6 - 24c + 24c²; \begin{equation}2)-12\left ( x+\frac{1}{3}y \right )^{2}=\end{equation} \begin{equation}=-12\left ( x^{2}+\frac{2}{3}xy+\frac{1}{9}y^{2} \right )=\end{equation} \begin{equation}=-12x^{2}-8xy-\frac{4}{3}y^{2};\end{equation} 3) a(a - 6b)² =
= a(a² - 12ab + 36b²) =
= a³ - 12a²b + 36ab²; \begin{equation}4)5b\left ( b^{2}+7b \right )^{2}=\end{equation} \begin{equation}=5b\left ( b^{4}+14b^{3}+49b^{2} \right )=\end{equation} \begin{equation}=5b^{5}+70b^{4}+245b^{3};\end{equation} 5) (a + 3)(a - 4)² =
= (a + 3)(a² - 8a + 16) =
= a³ - 8a² + 16a + 3a² - 24a + 48 =
= a³ - 5a² - 8a + 48;
6) (2x + 4)²(x - 8) =
= (4x² + 16x + 16)(x - 8) =
= 4x³ - 32x² + 16x² - 128x + 16x - 128 =
= 4x³ - 16x² - 112x - 128; \begin{equation}7)\left ( a-5 \right )^{2}\left ( a+5 \right )^{2}=\end{equation} \begin{equation}=\left ( \left ( a-5 \right )\left ( a+5 \right ) \right )^{2}=\end{equation} \begin{equation}=\left ( a^{2}-25 \right )^{2}=\end{equation} \begin{equation}=a^{4}-50a^{2}+625;\end{equation} \begin{equation}8)\left ( 3x+4y \right )^{2}\left ( 3x-4y \right )^{2}=\end{equation} \begin{equation}=\left ( \left ( 3x+4y \right ) \left ( 3x-4y \right )\right )^{2}=\end{equation} \begin{equation}=\left ( 9x^{2}-16y^{2} \right )^{2}=\end{equation} \begin{equation}=81x^{4}-288x^{2}y^{2}+256y^{4}.\end{equation}