\[\boxed{\text{675.}\text{\ }еуроки - ответы\ на\ пятёрку}\]
Пояснение.
Решение.
\[\textbf{а)}\ 14x + 21y = 7 \cdot (2x + 3y)\]
\[\textbf{б)}\ 15a + 10b = 5 \cdot (3a + 2b)\]
\[\textbf{в)}\ 8ab - 6ac = 2a(4b - 3c)\]
\[\textbf{г)}\ 9xa + 9xb = 9x(a + b)\]
\[\textbf{д)}\ 6ab - 3a = 3a(2b - 1)\]
\[\textbf{е)}\ 4x - 12x^{2} = 4x(1 - 3x)\]
\[\textbf{ж)}\ m^{4} - m^{2} = m²(m^{2} - 1)\]
\[\textbf{з)}\ c³ + c^{4} = c³(1 + c)\]
\[\textbf{и)}\ 7x - 14x^{3} = 7x(1 - 2x^{2})\]
\[\boxed{\text{675\ (675).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[\textbf{а)}\ b - a = - (a - b) = - 0,5\]
\[\textbf{б)}\ \frac{1}{b - a} = \frac{1}{- (a - b)} = - \frac{1}{0,5} =\]
\[= - 2\]
\[\textbf{в)}\ (a - b)^{2} = {0,5}^{2} = 0,25\]
\[\textbf{г)}\ (b - a)^{2} = \left( - (a - b) \right)^{2} =\]
\[= ( - 0,5)^{2} = 0,25\]
\[\textbf{д)}\ (a - b)^{3} = (0,5)^{3} = 0,125\]
\[\textbf{е)}\ \ (b - a)^{3} = \left( - (a - b) \right)^{3} =\]
\[= ( - 0,5)^{3} = - 0,125\]