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Solve the following equations, using inv...

Solve the following equations, using inverse of a matrix :
`{:(3x-2y+3z=8),(2x+y-z=1),(4x-3y+2z=4):}`

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To solve the equations using the inverse of a matrix, we will follow these steps: ### Step 1: Write the equations in matrix form The given equations are: 1. \(3x - 2y + 3z = 8\) 2. \(2x + y - z = 1\) 3. \(4x - 3y + 2z = 4\) We can express this in the matrix form \(AX = B\), where: \[ A = \begin{pmatrix} 3 & -2 & 3 \\ 2 & 1 & -1 \\ 4 & -3 & 2 \end{pmatrix}, \quad X = \begin{pmatrix} x \\ y \\ z \end{pmatrix}, \quad B = \begin{pmatrix} 8 \\ 1 \\ 4 \end{pmatrix} \] ### Step 2: Find the inverse of matrix \(A\) To find the inverse of matrix \(A\), we need to calculate the determinant of \(A\) first. #### Step 2.1: Calculate the determinant of \(A\) The determinant of a \(3 \times 3\) matrix is calculated as follows: \[ \text{det}(A) = a(ei - fh) - b(di - fg) + c(dh - eg) \] For our matrix \(A\): \[ \text{det}(A) = 3(1 \cdot 2 - (-1) \cdot (-3)) - (-2)(2 \cdot 2 - (-1) \cdot 4) + 3(2 \cdot (-3) - 1 \cdot 4) \] Calculating each term: - First term: \(3(2 - 3) = 3(-1) = -3\) - Second term: \(-2(4 - 4) = -2(0) = 0\) - Third term: \(3(-6 - 4) = 3(-10) = -30\) So, \[ \text{det}(A) = -3 + 0 - 30 = -33 \] #### Step 2.2: Find the adjoint of \(A\) The adjoint of a matrix is the transpose of the cofactor matrix. We will calculate the cofactors for each element of \(A\). Calculating cofactors: - \(C_{11} = \text{det}\begin{pmatrix} 1 & -1 \\ -3 & 2 \end{pmatrix} = (1)(2) - (-1)(-3) = 2 - 3 = -1\) - \(C_{12} = -\text{det}\begin{pmatrix} 2 & -1 \\ 4 & 2 \end{pmatrix} = -(2 \cdot 2 - (-1)(4)) = -(4 + 4) = -8\) - \(C_{13} = \text{det}\begin{pmatrix} 2 & 1 \\ 4 & -3 \end{pmatrix} = (2)(-3) - (1)(4) = -6 - 4 = -10\) Continuing this process for all elements, we find the cofactor matrix \(C\): \[ C = \begin{pmatrix} -1 & -8 & -10 \\ -1 & 10 & 6 \\ -1 & -8 & 7 \end{pmatrix} \] Now, take the transpose to find the adjoint: \[ \text{adj}(A) = C^T = \begin{pmatrix} -1 & -1 & -1 \\ -8 & 10 & -8 \\ -10 & 6 & 7 \end{pmatrix} \] #### Step 2.3: Calculate \(A^{-1}\) Using the formula \(A^{-1} = \frac{1}{\text{det}(A)} \cdot \text{adj}(A)\): \[ A^{-1} = \frac{1}{-33} \begin{pmatrix} -1 & -1 & -1 \\ -8 & 10 & -8 \\ -10 & 6 & 7 \end{pmatrix} = \begin{pmatrix} \frac{1}{33} & \frac{1}{33} & \frac{1}{33} \\ \frac{8}{33} & -\frac{10}{33} & \frac{8}{33} \\ \frac{10}{33} & -\frac{6}{33} & -\frac{7}{33} \end{pmatrix} \] ### Step 3: Solve for \(X\) Now, we can find \(X\) using \(X = A^{-1}B\): \[ X = \begin{pmatrix} \frac{1}{33} & \frac{1}{33} & \frac{1}{33} \\ \frac{8}{33} & -\frac{10}{33} & \frac{8}{33} \\ \frac{10}{33} & -\frac{6}{33} & -\frac{7}{33} \end{pmatrix} \begin{pmatrix} 8 \\ 1 \\ 4 \end{pmatrix} \] Calculating the multiplication: 1. First row: \(\frac{1}{33}(8) + \frac{1}{33}(1) + \frac{1}{33}(4) = \frac{8 + 1 + 4}{33} = \frac{13}{33}\) 2. Second row: \(\frac{8}{33}(8) - \frac{10}{33}(1) + \frac{8}{33}(4) = \frac{64 - 10 + 32}{33} = \frac{86}{33}\) 3. Third row: \(\frac{10}{33}(8) - \frac{6}{33}(1) - \frac{7}{33}(4) = \frac{80 - 6 - 28}{33} = \frac{46}{33}\) Thus, we have: \[ X = \begin{pmatrix} \frac{13}{33} \\ \frac{86}{33} \\ \frac{46}{33} \end{pmatrix} \] ### Final Solution The values of \(x\), \(y\), and \(z\) are: \[ x = \frac{13}{33}, \quad y = \frac{86}{33}, \quad z = \frac{46}{33} \]
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MODERN PUBLICATION-DETERMINANTS-Exercise 4(h) (LONG ANSWER TYPE QUESTIONS)
  1. Solve the following equations, using inverse of a matrix : {:(x+y+z=...

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  2. Solve the following equations, using inverse of a matrix : {:(5x-y+z...

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  3. Solve the following equations, using inverse of a matrix : {:(3x-2y+...

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  4. Solve the following equations, using inverse of a matrix : {:(3x-y+z...

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  5. Solve the following equations, using inverse of a matrix : {:(4x+3y+...

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  6. 2/x+3/y+10/z=4, 4/x-6/y+5/z=1, 6/x+9/y-20/z=2

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  7. Solve the following system of equations : {:((1)/(x)-(1)/(y)+(2)/(z)...

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  8. Solve the following system of equations : {:((1)/(x)-(1)/(y)+(2)/(z)...

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  9. If A=(2-3 5 3 2-4 1 1-2), find A^(-1) . Using A^(-1) solve the fol...

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  10. If A=((2,-3,5),(3,2,-4),(1,1,-2)) find A^(-1). Use it to solve the sys...

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  11. If A=[[3,2,1],[4,-1,2],[7,3,-3]] then find A^(-1) and hence solve the...

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  12. If A=[{:(3,1,2),(3,2,-3),(2,0,-1):}] , find A^(-1). Hence, solve the s...

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  13. If A=[{:(1,1,1),(1,0,2),(3,1,1):}], find A^(-1). Hence, solve the syst...

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  14. If A=((2,-3,5),(3,2,-4),(1,1,-2)) find A^(-1). Use it to solve the sys...

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  15. Given that A=[{:(1,-1,0),(2,3,4),(0,1,2):}] and B=[{:(2,2,-4),(-4,2,-4...

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  16. Given A=[{:(1 " "-1 " "1),(1 " "-2 " "-2),(2 " "1 " "3)...

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  17. Use product [1-1 2 0 2-3 3-2 4]\ \ [-2 0 1 9 2-3 6 1-2] to solve th...

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  18. Solve the following system of homogeneous equations: 2x+3y-z=0 x-y-2z...

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  19. Solve the following system of homogeneous linear equations by matri...

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  20. Solve following system of homogeneous linear equations: x+y-2z=0,\ ...

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