65 lines
1.1 KiB
Markdown
65 lines
1.1 KiB
Markdown
---
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title: 3 by 3 Determinants
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localeTitle: 3乘3的决定因素
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---
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## 3乘3的决定因素
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考虑以下矩阵,我们将其称为A:
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一个
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b
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C
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d
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Ë
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F
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G
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H
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一世
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然后,表示为_det(A)_的该矩阵的行列式由下式给出:
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_det(A)= a \*(e \* i - h \* f) - b \*(d \* i - f \* g)+ c \*(d \* h - e \* g)_
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请记住上面表达式中的操作顺序。
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例如,考虑以下矩阵,我们称之为B:
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1
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2
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3
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0
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\-3
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五
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\-10
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4
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7
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_det(B)_由上式给出。我们应用以下公式:
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_det(B)= 1 \*(( - 3)\* 7 - 5 \* 4) - 2 \*(0 \* 7 - 5 \*( - 10))+ 3 \*(0 \* 4 - ( - 3)\*( - 10) ))_ ,我们简化为:
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_det(B)= 1 \*(( - 21) - 20) - 2 \*(0 - ( - 50))+ 3 \*(0 - (30))_ ,我们简化为:
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_det(B)=( - 41) - 100 - 90 = -231_
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#### 更多信息:
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* MathIsFun上[矩阵](https://www.mathsisfun.com/algebra/matrix-determinant.html)的行列式
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* [3x3行列式计算器](http://www.wolframalpha.com/widgets/view.jsp?id=7fcb0a2c0f0f41d9f4454ac2d8ed7ad6)
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* 维基百科上的[决定因素](https://en.wikipedia.org/wiki/Determinant) |