第14章 14.6

(1)

$\left(\begin{array}{cc|c} 1 & -2 & 0 \\ 2 & 1 & 5 \end{array}\right) \to \left(\begin{array}{cc|c} 1 & -2 & 0 \\ 0 & 5 & 5 \end{array}\right) \to \left(\begin{array}{cc|c} 1 & -2 & 0 \\ 0 & 1 & 1 \end{array}\right) \to \left(\begin{array}{cc|c} 1 & 0 & 2 \\ 0 & 1 & 1 \end{array}\right)$

これから $(2,1)$

(2)

$\left(\begin{array}{cc|c} 1 & 2 & 4 \\ 3 & -2 & 2 \end{array}\right) \to \left(\begin{array}{cc|c} 1 & 2 & 4 \\ 0 & -8 & -10 \end{array}\right) \to \left(\begin{array}{cc|c} 2 & 4 & 8 \\ 0 & 4 & 5 \end{array}\right) \to \left(\begin{array}{cc|c} 2 & 0 & 3 \\ 0 & 4 & 5 \end{array}\right) \to \left(\begin{array}{cc|c} 1 & 0 & \dfrac{3}{2} \\ 0 & 1 & \dfrac{5}{4} \end{array}\right)$

これから $\left(\dfrac{3}{2}, \dfrac{5}{4}\right)$

(3)

$\left(\begin{array}{cc|c} 2 & 3 & -7 \\ 3 & -5 & 37 \end{array}\right) \to \left(\begin{array}{cc|c} 2 & 3 & -7 \\ 0 & -19 & 95 \end{array}\right) \to \left(\begin{array}{cc|c} 2 & 3 & -7 \\ 0 & 1 & -5 \end{array}\right) \to \left(\begin{array}{cc|c} 2 & 0 & 8 \\ 0 & 1 & -5 \end{array}\right) \to \left(\begin{array}{cc|c} 1 & 0 & 4 \\ 0 & 1 & -5 \end{array}\right)$

これから $(4,-5)$

(4)

$\left(\begin{array}{cc|c} 7 & 1 & 39 \\ 6 & 2 & 38 \end{array}\right) \to \left(\begin{array}{cc|c} 7 & 1 & 39 \\ -8 & 0 & -40 \end{array}\right) \to \left(\begin{array}{cc|c} 7 & 1 & 39 \\ 1 & 0 & 5 \end{array}\right) \to \left(\begin{array}{cc|c} 0 & 1 & 4 \\ 1 & 0 & 5 \end{array}\right)$

これから $(5,4)$