[tex]\begin{equation*} \begin{cases} a + 2b + 3c + 4d + 5e = 0 \\ a + 3b + c + 2d + 4e = 1\\ a + 3b + 2c + 3d + 3e = 2 \\ a + 3b + 2c + d + e = 3 \\ a +3b + 2c + d + 2e = 4 \end{cases}\end{equation*}[/tex]
Заметим, что (5) - (4):
[tex]e = 1[/tex]
Подставим e:
[tex]\begin{equation*} \begin{cases} a + 2b + 3c + 4d = -5 \\ a + 3b + c + 2d = -3\\ a + 3b + 2c + 3d = -1 \\ a + 3b + 2c + d = 2\end{cases}\end{equation*}[/tex]
Теперь (3) - (4):
[tex]2d = -3\\d= -1.5[/tex]
подставим d:
[tex]\begin{equation*} \begin{cases} a + 2b + 3c = 1 \\ a + 3b + c = 0\\ a + 3b + 2c = 3.5 \end{cases}\end{equation*}[/tex]
(3) - (2):
[tex]c = 3.5[/tex]
подставим c:
[tex]\begin{equation*} \begin{cases} a + 2b = -9.5 \\ a + 3b = -3.5 \end{cases}\end{equation*}[/tex]
Answers & Comments
Ответ:
a = -21.5, b = 6, c = 3.5, d = -1.5 e = 1
Объяснение:
[tex]\begin{equation*} \begin{cases} a + 2b + 3c + 4d + 5e = 0 \\ a + 3b + c + 2d + 4e = 1\\ a + 3b + 2c + 3d + 3e = 2 \\ a + 3b + 2c + d + e = 3 \\ a +3b + 2c + d + 2e = 4 \end{cases}\end{equation*}[/tex]
Заметим, что (5) - (4):
[tex]e = 1[/tex]
Подставим e:
[tex]\begin{equation*} \begin{cases} a + 2b + 3c + 4d = -5 \\ a + 3b + c + 2d = -3\\ a + 3b + 2c + 3d = -1 \\ a + 3b + 2c + d = 2\end{cases}\end{equation*}[/tex]
Теперь (3) - (4):
[tex]2d = -3\\d= -1.5[/tex]
подставим d:
[tex]\begin{equation*} \begin{cases} a + 2b + 3c = 1 \\ a + 3b + c = 0\\ a + 3b + 2c = 3.5 \end{cases}\end{equation*}[/tex]
(3) - (2):
[tex]c = 3.5[/tex]
подставим c:
[tex]\begin{equation*} \begin{cases} a + 2b = -9.5 \\ a + 3b = -3.5 \end{cases}\end{equation*}[/tex]
(2) - (1):
[tex]b = -3.5 + 9.5 = 6[/tex]
И найдём a:
[tex]a + 2b = -9.5\\a + 12 = -9.5\\a = -21.5[/tex]