Cofactor expansion Examples
Example: $3 \times 3$
Expand
by cofactors
(a)
|
along the first column,
|
(b)
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along the second column,
|
(c)
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along the third column,
|
(d)
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along the first row,
|
(e)
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along the second row,
|
(f)
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along the third row.
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Answer
(a)
Cofactor expansion along the first column:
(b)
Cofactor expansion along the second column:
(c)
Cofactor expansion along the third column:
(d)
Cofactor expansion along the first row:
(e)
Cofactor expansion along the second row:
(f)
Cofactor expansion along the third row:
Example: $4 \times 4$
Expand
by cofactors
(a)
|
along the first column,
|
(b)
|
along the second column,
|
(c)
|
along the third column,
|
(d)
|
along the fourth column,
|
(e)
|
along the first row,
|
(f)
|
along the second row,
|
(g)
|
along the third row,
|
(h)
|
along the fourth row.
|
Answer
(a)
Cofactor expansion along the first column:
(b)
Cofactor expansion along the second column:
(c)
Cofactor expansion along the third column:
(d)
Cofactor expansion along the fourth column:
(e)
Cofactor expansion along the first row:
(f)
Cofactor expansion along the second row:
(g)
Cofactor expansion along the third row:
(h)
Cofactor expansion along the fourth row: