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anonymous
 one year ago
I don't understand this question.
Calculate the second term in the cofactor expansion along the third row for the matrix:
[[1,1,1,1],[1,1,2,0],[1,1,0,2],[1,1,1,1]]
anonymous
 one year ago
I don't understand this question. Calculate the second term in the cofactor expansion along the third row for the matrix: [[1,1,1,1],[1,1,2,0],[1,1,0,2],[1,1,1,1]]

This Question is Closed

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[\left[\begin{matrix}1 & 1 & 1 & 1 \\ 1 & 1 & 2 & 0 \\ 1 & 1 & 0 & 2 \\ 1 & 1 & 1 & 1\end{matrix}\right]\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So the third row would be [1, 1, 0, 2]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Second term being 1

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So do I just use 1 times the rest of the matrix?

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3\[\left[\begin{matrix}1 & 1 & 1 & 1 \\ 1 & 1 & 2 & 0 \\ 1 & \color{red}{1} & 0 & 2 \\ 1 & 1 & 1 & 1\end{matrix}\right]\]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I guess you can take the determinant?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Take the determinant of the original matrix and times that by 1?

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3whats the definition of "term" that your professor uses ?

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3does the determinant has \(4!=24\) terms or just \(4\) terms according to your prof ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I think she'd say that that'd be just 4 terms.

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3** then, you just need to find the cofactor of 1, which is at 3,2 location, then multiply that by 1

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3** cofactor of \(A_{32}\)= \((1)^{3+2}\begin{vmatrix}1&1&1\\1&2&0\\1&1&1\end{vmatrix}\)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Okay, I am obviously not understanding this question because the answer I got was 0...

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3Right, I think your prof wants the first term out of those 24 terms in the determinant

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0There's a similar question on this website that went unanswered: http://openstudy.com/study#/updates/5039e2afe4b043c156a3277c

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0How did they obtain 20 in this example? https://au.answers.yahoo.com/question/index?qid=20120826032029AANjdNA

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3the answer is either 0 or 2 0 if you consider 4 terms in the determinant 2 if you consider 24 terms

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3yahoo answers is not that reliable..

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Aha, I know, I was just trying to work out how they managed to get 20 that's all

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3they got 40 right ?

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3remember how to find cofactor of a term ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Yes, but it's a bit hard to write it all on here.

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3[3,1,2,1] [2,2,1,2] [2,2,2,1] [1,3,2,1] to find the cofactor of 2 at position 3,2 you simply find the determinant of the small matrix obtained by deleting 3rd row and second column, then fix the sign

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3removing 3rd row and 2nd column, [3,2,1] [2,1,2] [1,2,1]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0And then multiplying all that by 2.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0What I don't understand is how they ended up getting (2) x (20) to get 40.

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3before that, multiply the determinant by \((1)^{3+2}\) to get the cofactor

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3what do you get for determinant of [3,2,1] [2,1,2] [1,2,1]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So for my particular question, the determinant of the submatrix is just 0, does this mean that the answer is just 0 then?

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3let me just quote my previous reply ``` the answer is either 0 or 2 0 if you consider 4 terms in the determinant 2 if you consider 24 terms ```

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Yeah, I remember reading that, I was just confused as to how you managed to get 2 as well if I considered 24 terms rather than 4

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3lets work it step by step

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3how many terms are there in the determinant of a 2x2 matrix ?

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3\[ \begin{vmatrix}a&b\\c&d\\\end{vmatrix} = adbc\] two terms, right ?

ganeshie8
 one year ago
Best ResponseYou've already chosen the best response.3how about the determinant of a \(3\times 3\) matrix, how many terms ?
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