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基礎微積分

綜合除法

來源

\[
(a_3x^3 + a_2x^2 + a_1x + a_0) = (b_2x^2 + b_1x + b_0)(x - a) + r        
\]
\[
(a_3x^3 + a_2x^2 + a_1x + a_0) \div (x - a)=(b_2x^2 + b_1x + b_0)...r
\]

綜合除法過程:

\[
\begin{array}{r|rrrr}
a & a_3 & a_2 & a_1 & a_0 \\
  &     & b_2a & b_1a & b_0a \\
\hline
  & b_2 & b_1 & b_0 & r \\
\end{array}
\]

範例

欲計算

\[
(2x^3 - 3x^2 - 4x + 5) \div  (x - 2)     
\]

綜合除法

\[
\begin{array}{r|rrrr}
2 & 2 & -3 & -4 & 5 \\
  &   & 4  &  2 & -4 \\
\hline
  & 2 &  1 & -2 & 1 \\
\end{array}
\]

結果:

\( 商 = 2x^2 + x - 2 \)
\( 餘數 = 1 \)