вправа 1171 гдз 7 клас алгебра Мерзляк Полонський
7 клас ➠ алгебра ➠ Мерзляк Полонський
Вправа 1171
Відповідь:
1) 6x² + (2y - 3x)(2y + 3x) =
= 6x² + 4y² - 9x² =
= 4y² - 3x²;
2) (a + 2)(a - 3) - (4 - a)(a + 4) =
= a² - a - 6 - 16 + a² =
= 2a² - a - 22;
3) (5 - 2x)(5 + 2x) - (3 - 2x)(4 - 2x) =
= 25 - 4x² - (12 - 6x - 8x + 4x²) =
= 25 - 4x² - 12 + 14x - 4x² =
= -8x² + 14x + 13; \begin{equation}4)\left ( 2ab+1 \right )\left ( 2ab-1 \right )\end{equation} \begin{equation}\left ( 16a^{4}b^{4}+1 \right )\left ( 4a^{2}b^{2}+1 \right )=\end{equation} \begin{equation}=\left ( 4a^{2}b^{2}-1 \right )\left ( 4a^{2}b^{2}+1 \right )\end{equation} \begin{equation}\left ( 16a^{4}b^{4}+1 \right )=\end{equation} \begin{equation}=\left ( 16a^{4}b^{4}-1 \right )\left ( 16a^{4}b^{4}+1 \right )=\end{equation} \begin{equation}=256a^{8}b^{8}-1.\end{equation}
1) 6x² + (2y - 3x)(2y + 3x) =
= 6x² + 4y² - 9x² =
= 4y² - 3x²;
2) (a + 2)(a - 3) - (4 - a)(a + 4) =
= a² - a - 6 - 16 + a² =
= 2a² - a - 22;
3) (5 - 2x)(5 + 2x) - (3 - 2x)(4 - 2x) =
= 25 - 4x² - (12 - 6x - 8x + 4x²) =
= 25 - 4x² - 12 + 14x - 4x² =
= -8x² + 14x + 13; \begin{equation}4)\left ( 2ab+1 \right )\left ( 2ab-1 \right )\end{equation} \begin{equation}\left ( 16a^{4}b^{4}+1 \right )\left ( 4a^{2}b^{2}+1 \right )=\end{equation} \begin{equation}=\left ( 4a^{2}b^{2}-1 \right )\left ( 4a^{2}b^{2}+1 \right )\end{equation} \begin{equation}\left ( 16a^{4}b^{4}+1 \right )=\end{equation} \begin{equation}=\left ( 16a^{4}b^{4}-1 \right )\left ( 16a^{4}b^{4}+1 \right )=\end{equation} \begin{equation}=256a^{8}b^{8}-1.\end{equation}