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10. Optional Question. What would be the most efficient way to compute the determinant of an n by n matrix where n is large? Assume the matrix entries are all non-zero so you cannot take advantage of sparsity. Briefly explain why the method you suggest would be much more efficient than cofactor expansion. Hints: Recall that in general for an n by n matrix cofactor expansion to compute the determinant requires $n!$ operations. Also recall that the if a matrix is upper triangular, you can compute the determinant as the product of the diagonal elements. In addition, recall that row reduction to echlon form does not change the value of the determinant. (Assume no row interchanges or scaling is used.)

          10. Optional Question. What would be the most efficient way to compute the determinant of an n by n matrix where n is large? Assume the matrix entries are all non-zero so you cannot take advantage of sparsity. Briefly explain why the method you suggest would be much more efficient than cofactor expansion.
Hints: Recall that in general for an n by n matrix cofactor expansion to compute the determinant requires $n!$ operations. Also recall that the if a matrix is upper triangular, you can compute the determinant as the product of the diagonal elements. In addition, recall that row reduction to echlon form does not change the value of the determinant. (Assume no row interchanges or scaling is used.)
        
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10. Optional Question. What would be the most efficient way to compute the determinant of an n by n matrix where n is large? Assume the matrix entries are all non-zero so you cannot take advantage of sparsity. Briefly explain why the method you suggest would be much more efficient than cofactor expansion.
Hints: Recall that in general for an n by n matrix cofactor expansion to compute the determinant requires n! operations. Also recall that the if a matrix is upper triangular, you can compute the determinant as the product of the diagonal elements. In addition, recall that row reduction to echlon form does not change the value of the determinant. (Assume no row interchanges or scaling is used.)

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Elementary and Intermediate Algebra
Elementary and Intermediate Algebra
Alan S. Tussy, R. David Gustafson 5th Edition
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Please solve it quickly!!!! 10. Optional Question. What would be the most efficient way to compute the determinant of an n by n matrix where n is large? Assume the matrix entries are all non-zero, so you cannot take advantage of sparsity. Briefly explain why the method you suggest would be much more efficient than cofactor expansion. Hints: Recall that in general, for an n by n matrix, cofactor expansion to compute the determinant requires n! operations. Also, recall that if a matrix is upper triangular, you can compute the determinant as the product of the diagonal elements. In addition, recall that row reduction to echelon form does not change the value of the determinant. (Assume no row interchanges or scaling is used.)
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00:30 We are considering the lu factorization a equal to lu.
00:31 L321 and u equal to this is an upper triangular matrix with entries u11 u1 2 u2 u2 0 0 0 03 0 0 -3 so now we have to find the determinant a so determinant a equal to determinant of l u so which is equal to determinant of l multiplied by determinant of u and the determinant of l is the one because it is the unit matrix like okay and determinant of a is equal to determinant of you from this we can say the determinant of a product of the diagonal elements from this we can have this which is equal to product uii hence determinant of a is equal to product uii when determinant a is equal to we will get a 4 by 4 matrix as u11, u12, u13, u14, 0, u2, u2, u23, u24, u22, u22, u24, 0 -33, u3, u34, 0 -0 -0 -0 -4.
01:49 Okay, so which is equal to u11 into determinant of u -22 multiplied by u -3 -3 minus u4, multiplied by u -u -44 minus 0...
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