ГДЗ по алгебре 9 класс Макарычев Задание 844

\[\boxed{\text{844\ (844).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]

\[\textbf{а)}\ C_{9}^{4} = \frac{9!}{(9 - 4)!} = \frac{9!}{5!} =\]

\[= 6 \cdot 7 \cdot 8 \cdot 9 = 3024\ способа.\]

\[\textbf{б)}\ C_{9}^{3} = \frac{9!}{(9 - 3)!} = \frac{9!}{6!} =\]

\[= 7 \cdot 8 \cdot 9 = 504\ способа.\]

\[\boxed{\text{844.}\text{\ }\text{ОК\ ГДЗ\ -\ домашка\ на\ 5}}\]

\[x^{8} + x^{6} - 4x^{4} + x^{2} + 1 =\]

\[= x^{8} - 2x^{4} + 1 + x^{6} - 2x^{4} + x^{2} =\]

\[= \left( x^{4} - 1 \right)^{2} + x^{6} - 2x^{4} + x^{2} =\]

\[= \left( x^{4} - 1 \right)^{2} + x^{2}\left( x^{4} - 2x^{2} + 1 \right) =\]

\[= \left( x^{4} - 1 \right)^{2} + x^{2}\left( x^{2} - 1 \right)^{2},\]

\[\left( x^{4} - 1 \right)^{2} + x^{2}\left( x^{2} - 1 \right)^{2} \geq 0 \Longrightarrow\]

\[\Longrightarrow при\ любом\ x.\]