\[\boxed{\text{348\ (348).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[\textbf{а)}\ x^{3} + 11x - 108 = 0\]
\[x_{1} = 4 \Longrightarrow корень.\ \]
\[Схема\ Горнера:\]
\[1\] | \[0\] | \[11\] | \[- 108\] | |
---|---|---|---|---|
\[4\] | \[1\] | \[4\] | \[27\] | \[0\] |
\[(x - 4)\left( x^{2} + 4x + 27 \right) = 0\]
\[x^{2} + 4x + 27 = 0\]
\[D = 4 - 27 < 0 \Longrightarrow корней\ нет.\]
\[\textbf{б)}\ x^{5} + 6x + 44 = 0\]
\[x_{1} = - 2 \Longrightarrow корень\ уравнения.\]
\[Схема\ Горнера:\]
\[1\] | \[0\] | \[0\] | \[0\] | \[6\] | \[44\] | |
---|---|---|---|---|---|---|
\[- 2\] | \[1\] | \[- 2\] | \[4\] | \[- 8\] | \[22\] | \[0\] |
\[(x + 2)\left( x^{4} - 2x^{3} + 4x^{2} - 8x + 22 \right) = 0\]
\[x^{4} - 2x^{3} + 4x^{2} - 8x + 22 =\]
\[= \left( x - \frac{1}{2} \right)^{4} + 2,5x^{2} - 7,5x +\]
\[+ 22 - \frac{1}{16} > 0\]
\[\Longrightarrow x = - 2.\]
\[Ответ:а)\ 4;\ \ б) - 2.\]