Решебник по алгебре 9 класс Макарычев Задание 561

\[\boxed{\text{561\ (561).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]

\[c_{1} = - 1,\ \ c_{2} = 0,\ \ c_{3} = - 1,\ \ \]

\[c_{4} = 0,\ \ c_{5} = - 1,\]

\[c_{6} = 0,\ \ c_{7} = - 1,\ \ c_{8} = 0,\ \ \]

\[c_{25} = - 1,\ \ c_{200} = 0,\]

\[c_{253} = - 1,\ \ c_{2k} = 0,\ \ \]

\[c_{2k + 1} = - 1.\]

\[\boxed{\text{561.}\text{\ }\text{ОК\ ГДЗ\ -\ домашка\ на\ 5}}\]

\[Пусть\ a = x;\ \ b = x + d;\ \ \]

\[тогда\ \ c = x + 2d;\]

\[a^{2} + ac + c^{2} =\]

\[= x^{2} + x(x + 2d) + (x + 2d)^{2} =\]

\[= x^{2} + x^{2} + 2xd + x^{2} + 4xd + 4d^{2} =\]

\[= 3x^{2} + 6xd + 4d^{2} =\]

\[= \left( 3x^{2} + 3dx + d^{2} \right) + \left( 3dx + 3d^{2} \right);\]

\[членами\ арифметической\ \]

\[прогрессии.\]