вправа 510 гдз 7 клас алгебра Мерзляк Полонський

Відповідь:

1) a(a - 2)(a + 2) =
= a(a² - 4) = a³ - 4a;
2) -3(x + 3)(x - 3) =
= -x(x² - 9) = 9x - x³; \begin{equation}3)7b^{2}\left ( b+4 \right )\left ( b-4 \right )=\end{equation} \begin{equation}=7b^{2}\left ( b^{2}-16 \right )=\end{equation} \begin{equation}=7b^{4}-112b^{2};\end{equation} \begin{equation}4)\left ( c-d \right )\left ( c+d \right )\left ( c^{2}+d^{2} \right )=\end{equation} \begin{equation}=\left ( c^{2}-d^{2} \right )\left ( c^{2}+d^{2} \right )=\end{equation} \begin{equation}=c^{4}-d^{4};\end{equation} \begin{equation}5)\left ( 2a-1 \right )\left ( 2a+1 \right )\left ( 4a^{2}+1 \right )=\end{equation} \begin{equation}=\left ( 4a^{2}-1 \right )\left ( 4a^{2}+1 \right )=\end{equation} \begin{equation}=16a^{4}-1;\end{equation} \begin{equation}6)\left ( c^{3}-5 \right )\left ( c^{3}+5 \right )\left ( c^{6} +25\right )=\end{equation} \begin{equation}=\left ( c^{6}-25 \right )\left ( c^{6}+25 \right )=\end{equation} \begin{equation}=c^{12}-625.\end{equation}