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If the matrix is { a1 b1 c1}

{a2 b2 c2}

{a3 b3 c3}

then the determinant is

a1b2c3 + b1c2a3 + c1a2b3 - (c1b2a3 + a1c2b3 + b1a2c3)

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Q: What is the formula for the determinant of a 3 x 3 matrix?
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What is the determinant rank of the determinant of 123456 its a 2 x 3 matrix?

A determinant is defined only for square matrices, so a 2x3 matrix does not have a determinant.Determinants are defined only for square matrices, so a 2x3 matrix does not have a determinant.


What is the formula for determinant of a 3x3 matrix?

To answer this question, let me establish an example 3 x 3 matrix named "A": A= [a b c] [d e f] [g h i] The formula I will give you, called co-factor expansion, works for any size square matrix, so you could use it to find the determinant of a 2 x 2, 3 x 3, all the way up to an n x n matrix. To find the determinant, pick any row or column in the matrix. It will make your work much easier if you choose a row or column that has many zeroes in it. A general notation that is often used to find the determinant of a matrix is to use straight bars in place of the brackets surrounding the matrix contents. So, if I was to say mathematically that I was finding the determinant of the above example matrix, I could write it as: det(A)= |a b c| |d e f| |g h i| This notation will be used in the formula, so it is important to know this. For the sake of an arbitrary example, let us suppose I chose Row 1 of the matrix as my chosen row. To find the determinant of this matrix, I will perform the following calculation: (-1)2(a)|e f| + (-1)3(b)|d f| + (-1)4(c)|d e| |h i| |g i| |g h| This is the specific application of this general formula to the example matrix: (-1)i+j(aij)det(A1) In this formula, i and j are the row and column addresses, respectively, of a given matrix element. So, like in our specific application, when Row 1 was chosen as our subject row, the first term was (-1)1+1(A11)det(A1). The element "a" is in the first row, first column of the matrix, mean i=1 and j=1, therefore the superscript of (-1) is 1+1=2. A11 is simply the value held in the address i=1, j=1 of the matrix A. For this application, A11 was "a". det(A1) is the determinant of the submatrix A1. This submatrix has no formal nomenclature, I simply call it this for ease of explanation. A1 is the matrix created by "crossing out" the row and column that belong to the matrix element A11. In this application, that means it is the submatrix that is left after crossing out a, b, c, d, and g, which is simply the 2 x 2 matrix e,f;h,i. Performing this same process for the remainder of the matrix elements in Row 1 will yield the determinant of the matrix. So, the "generalized" form of the specific application above is: (-1)1+1(A11)det(A1) + (-1)1+2(A12)det(A2) + (-1)1+3(A13)det(A3) where A1 is the submatrix created by crossing out Row 1 and Column 1, A2 is the submatrix created by crossing out Row 1 and Column 2, and A3 is the submatrix created by crossing out Row 1 and Column 3. A final note is how to calculate the determinants of the submatrices. For a 3 x 3 matrix, its submatrices are all 2 x 2. For 2 x 2 matrices, a simple formula exists that makes this easy: |a b| = (ad) - (bc) |c d| For higher-dimension matrices, the submatrices also become larger, making the computation much more intensive.


How do you find the inverse of A in system of linear equation and matrices?

First, we need to recall that a linear equation does not involve any products or roots of variables. All variables occur only to the first power and do not appear as arguments for trigonometric, logarithmic, or exponential functions. For example, x + √y = 4, y = sin x, and 2x + y - z + yz = 5 are not linear.To solve a system of equations such as3x + y = 52x - y = 3all information required for the solution is emboded in the augmented matrix (imagine that I put those information into a rectangular arrays)3 1 52 -1 3and that the solution can be obtained by performing appropriate operations on this matrix.The matrix of this system linear equations is a square matrix A such as3 12 -1Think this matrix asa bc dTo find an inverse of this square matrix A (2 x 2), we need to find a matrix B of the same size such that AB = I and BA = I, then A is said to be invertible and B is called the inverse of A. If no such a matrix can be found, then A is said to be singular.An invertible matrix has exactly one inverse.A square matrix A is invertible if ad - bc ≠ 0 (where ad - bc is the determinant)The formula of finding the inverse of a square matrix A isA-1 = [1/(ad - bc)][d -b the second row -c a](I'm sorry, I can't draw the arrays)So let's find the inverse of our example.A-1 = [1/(-3 -2)][-1 -1 the second row -2 3] = [-1/-5 -1/-5 the sec. row -2/-5 3/-5] =1/5 1/52/5 -3/5A n x m matrix cannot have an inverse. A n x n matrix may or may not have an inverse.To find the inverse of a n x n matrix we should to adjoin the identity matrix to the right side of A, thereby producing a matrix of the form [A | I]. Then we should apply row opperations to this matrix until the left side is reduced to I. This opperations will convert the right side to A-1, so the final matrix will have the form [I |A-1 ].(There are many other methods how to find the inverse of a n x n matrix, but I can't show them by examples. I am so sorry that I can't be so much useful to you).


How evaluate the following determinant by row operations 3 2 6 1 1 2 2 2 5?

determinant sign | | 3 2 6 + - + 1 1 2 - + - 2 2 5 + - + (don't forget the signs) Work with the second row: = (-1)|2 6, 2 5| + 1|3 6, 2 5| - 2|3 2, 2 2| (draw a vertical line, and a horizontal one at 1, 1, and 2 in the second row) = -1[2 x 5) - (6 x 2)] + [(3 x 5) - (6 x 2)] - 2[(3 x 2) - (2 x 2)] = (-1)(10 - 12) + (15 - 12) - (2)(6 - 4) = (-1)(-2) + 3 - (2)(2) = 2 + 3 - 4 = 1 Thus the value of the determinant is equal to 1.


What are the matrix method of linear systems?

Consider the linear system of equations AX = YwhereX is a n x 1 matrix of variables,Y is a n x 1 matrix of constants, andA is an n x n matrix of coefficients.Provided A is not a singular matrix, A has an inverse, A-1, an n x n matrix.Premultiplying by A-1 gives A-1AX = A-1Y or X = A-1Y, the solution to the linear system.

Related questions

What is the determinant rank of the determinant of 123456 its a 2 x 3 matrix?

A determinant is defined only for square matrices, so a 2x3 matrix does not have a determinant.Determinants are defined only for square matrices, so a 2x3 matrix does not have a determinant.


What does determinant mean in math?

That's a special calculation done on square matrices - for example, on a 2 x 2 matrix, or on a 3 x 3 matrix. For details, see the Wikipedia article on "Determinant".


How to find x in a 2×2 matrix with a given determinant.?

For a matrix A, A is read as determinant of A and not, as modulus of A. ... sum of two or more elements, then the given determinant can be expressed as the sum


How do you determine determinant of matrix using matlab?

d = det(x);


What is the formula for determinant of a 3x3 matrix?

To answer this question, let me establish an example 3 x 3 matrix named "A": A= [a b c] [d e f] [g h i] The formula I will give you, called co-factor expansion, works for any size square matrix, so you could use it to find the determinant of a 2 x 2, 3 x 3, all the way up to an n x n matrix. To find the determinant, pick any row or column in the matrix. It will make your work much easier if you choose a row or column that has many zeroes in it. A general notation that is often used to find the determinant of a matrix is to use straight bars in place of the brackets surrounding the matrix contents. So, if I was to say mathematically that I was finding the determinant of the above example matrix, I could write it as: det(A)= |a b c| |d e f| |g h i| This notation will be used in the formula, so it is important to know this. For the sake of an arbitrary example, let us suppose I chose Row 1 of the matrix as my chosen row. To find the determinant of this matrix, I will perform the following calculation: (-1)2(a)|e f| + (-1)3(b)|d f| + (-1)4(c)|d e| |h i| |g i| |g h| This is the specific application of this general formula to the example matrix: (-1)i+j(aij)det(A1) In this formula, i and j are the row and column addresses, respectively, of a given matrix element. So, like in our specific application, when Row 1 was chosen as our subject row, the first term was (-1)1+1(A11)det(A1). The element "a" is in the first row, first column of the matrix, mean i=1 and j=1, therefore the superscript of (-1) is 1+1=2. A11 is simply the value held in the address i=1, j=1 of the matrix A. For this application, A11 was "a". det(A1) is the determinant of the submatrix A1. This submatrix has no formal nomenclature, I simply call it this for ease of explanation. A1 is the matrix created by "crossing out" the row and column that belong to the matrix element A11. In this application, that means it is the submatrix that is left after crossing out a, b, c, d, and g, which is simply the 2 x 2 matrix e,f;h,i. Performing this same process for the remainder of the matrix elements in Row 1 will yield the determinant of the matrix. So, the "generalized" form of the specific application above is: (-1)1+1(A11)det(A1) + (-1)1+2(A12)det(A2) + (-1)1+3(A13)det(A3) where A1 is the submatrix created by crossing out Row 1 and Column 1, A2 is the submatrix created by crossing out Row 1 and Column 2, and A3 is the submatrix created by crossing out Row 1 and Column 3. A final note is how to calculate the determinants of the submatrices. For a 3 x 3 matrix, its submatrices are all 2 x 2. For 2 x 2 matrices, a simple formula exists that makes this easy: |a b| = (ad) - (bc) |c d| For higher-dimension matrices, the submatrices also become larger, making the computation much more intensive.


How do you figure out whether a matrix has a determinant?

Any n x n (square) matrix have a determinate. If it's not a square matrix, we don't have a determinate, or rather we don't care about the determinate since it can't be invertible.


Is it possible to solve for the determinant of a 3 x 4 matrix?

No. Determinants are only defined for square matrices.No. Determinants are only defined for square matrices.


What is a 9 cell matrix?

3 x 3 matrix


How do you get inverse of a matrix?

There are two main methods: both depend on a reasonable understanding of matrices and determinants.One way is to append an identity matrix to the right of the original matrix. So, given an n x n matrix A, create an n x 2n matrix A|I.Using only row operations, convert A into an identity matrix. Then the right hand side of A|I will be A-1Alternatively, calculate the determinant |A|Also calculate the determinants of all n-1 x n-1 sub-matrices where sijdenotes the determinant of the submatrix created when row i and column j are deleted.Let bij= sij*(-1)i+j/|A|.Then the matrix B = {bij} = A-1.


What is the difference between matrices and determinants?

Both matrix and determinants are the part of business mathematics. Both are useful for solving business problem. Both are helpful for calculation of each other. For calculation of inverse of matrix, we need to calculate the determinant. For calculating the value of 3X3 matrix or more matrix, we need to divide determinants in sub-matrix. but there are many differences between matrix and determinants which we can explain in following points. 1. Matrix is the set of numbers which are covered by two brackets. Determinants is also set of numbers but it is covered by two bars. 2. It is not necessary that number of rows will be equal to the number of columns in matrix. But it is necessary that number of rows will be equal to the number of columns in determinant. 3. Matrix can be used for adding, subtracting and multiplying the coefficients. Determinant can be used for calculating the value of x, y and z with Cramer's Rule. By Er. Hafijullah


What will be the dimensions of the new matrix formed by multiplying a 3 X 4 matrix and a 4 X 1 matrix?

3x1 matrix


How do i solve rank of a determinant?

Matrix inverses and determinants, square and nonsingular, the equations AX = I and XA = I have the same solution, X. This solution is called the inverse of A.