$$ 多項式x^3-8x^2+20x-17\\=a(x-1)(x-2)(x-3)+b(x-1)(x-2)+c(x-1)+d \\ , 求 a,b,c,d $$
$$ 方法一:用f(1),f(2),f(3),f(0)依序算出d,c,b,a $$
$$ 方法一:連續綜合除法-本質上和方法一相同 $$
$$ \begin{gathered} \left. {\underline {\, {\begin{array}{*{20}{c}} 1&{ - 8}&{ + 20}&{ - 17} \\ {}&{ + 1}&{ - 7}&{ + 13} \end{array}} \,}}\! \right| \begin{array}{*{20}{c}} {} \\ { + 1} \end{array} \hfill \\ \left. {\underline {\, {\begin{array}{*{20}{c}} 1&{ - 7}&{ + 13} \\ {}&{ + 2}&{ - 10} \end{array}} \,}}\! \right| \begin{array}{*{20}{c}} { - 4} \\ { + 2} \end{array}\begin{array}{*{20}{c}} { \to d} \\ {} \end{array} \hfill \\ \left. {\underline {\, {\begin{array}{*{20}{c}} 1&{ - 5} \\ {}&{ + 3} \end{array}} \,}}\! \right| \begin{array}{*{20}{c}} { + 3} \\ { + 3} \end{array}\begin{array}{*{20}{c}} { \to c} \\ {} \end{array} \hfill \\ \left. {\underline {\, 1 \,}}\! \right| \begin{array}{*{20}{c}} { - 2}&{ \to b} \end{array} \hfill \\ \end{gathered} $$
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