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How do you find the variable in this matrix 3 -2 5 a ...the determinant is 7?
Wiki User
∙ 10y ago
If it a 2x2 matrix, the determinant is 3*a - (-2)*5 = 3a + 10 = 7
So 3a = -3 so a = -1
Wiki User
∙ 10y ago
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How can you solve if the determinant of 3 by 3 matrix is 2?
It isn't clear what you want to solve for. If you want to find the matrix, there is not a unique solution - there are infinitely many matrices with the same 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 do you decide how many solutions a linear system in three variables has?
Put the coefficients of the variables into a 3x3 matrix, and take the determinant of the matrix. If the determinant is not zero, then there is one solution. If the determinant is zero, then there are infinite solutions or there is no solution. Think of a system of 2 variables, for simplicity. You have 2 equations and 2 variables (x & y). Each equation can be graphed as a straight line, hence the name 'linear system'. If the 2 lines are not parallel, then there will be only one point where they intersect, which is the one solution to the linear system. If they are parallel, then there is no solution(they never intersect), and if the two lines coincide, then infinite solutions(they intersect at every point). In both of the latter cases, the related matrix will have a determinant of zero.
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
Why does the rule of sarrus work only for a 3 by 3 matrix?
In theory, a 2x2 determinant requires the evaluation of 2 products, a 3x3 determinant requires 6 products, a 4x4 determinant requires 24 products (note: that is the factorial function). The Rule of Sarrus is just a convenient memory aid for this specific case.
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 can you solve if the determinant of 3 by 3 matrix is 2?
It isn't clear what you want to solve for. If you want to find the matrix, there is not a unique solution - there are infinitely many matrices with the same determinant.
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.
Is there an easy way by which I mean a way that requires less than half an hour and no higher math than Algebra 2 to find the determinant of a 5 by 5 matrix?
There is no easy way to find the determinant; it's long and tedious. There are computer programs available (like MATLAB) that will find the determinant. You'll find there probably won't be a large matrix in an exam if you're required to find the 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 do you find the area of a triangle using matrix methods?
Put the three points in a matrix with the last column with ones. Then find the determinant, then multiple by .5 Example: (1,1) (2,4)(4,2) 1 1 1 2 4 1 4 2 1 The determinant is: [(1*4*1)+(1*1*4)+(2*2*1)]-[(1*4*4)+(1*2*1)+(1*2*1)]=12-20= -8 Therefore you must multiple by -.5= 4
How do you decide how many solutions a linear system in three variables has?
Put the coefficients of the variables into a 3x3 matrix, and take the determinant of the matrix. If the determinant is not zero, then there is one solution. If the determinant is zero, then there are infinite solutions or there is no solution. Think of a system of 2 variables, for simplicity. You have 2 equations and 2 variables (x & y). Each equation can be graphed as a straight line, hence the name 'linear system'. If the 2 lines are not parallel, then there will be only one point where they intersect, which is the one solution to the linear system. If they are parallel, then there is no solution(they never intersect), and if the two lines coincide, then infinite solutions(they intersect at every point). In both of the latter cases, the related matrix will have a determinant of zero.
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.
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
Why does the rule of sarrus work only for a 3 by 3 matrix?
In theory, a 2x2 determinant requires the evaluation of 2 products, a 3x3 determinant requires 6 products, a 4x4 determinant requires 24 products (note: that is the factorial function). The Rule of Sarrus is just a convenient memory aid for this specific case.
Can someone help find the determinant of this 5x5 matrix?
sorry i didnt know how to type the matrix out basically the 5x5 matrix is... 1 2 5 0 1 2 3 7 1 9 1 2 3 0 3 0 0 1 0 0 3 2 -4 0 1 i understand that the 4th row/column is best to delete. but what do i do from here? please show step by step if you can :)
To find discriminant of a matrix?
Well, Im not sure if this is true for all matrices of all sizes, but for a 2x2 square matrix the discriminant is... dis(A) = tr(A)^2 - 4 det(A) The discriminant of matrix A is equal to the square of the trace of matrix A, minus four times the determinant of matrix A. I know this to be true for all 2x2 square matrice, but I have never seen any statement one way or the other for larger matrices. Thus, for matrix A = [ a, b; c, d ] tr(A) = a+d det(A) = ad-bc tr(A)^2 = a^2 + 2ad + d^2 4 det(A) = 4ad - 4bc dis(A) = a^2 - 2ad + 4bc + d^2
