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Consider the system of equations (a -1...

Consider the system of equations
`(a -1) x -y -z = 0`
`x -(b -1) y +z = 0`
`x + y - (c -1) z = 0`
Where a, b and c are non-zero real number
Statement1 : If x,y,z are not all zero, then `ab + bc + ca = abc`
Statement 2 : `abc ge 27`

A

Statement 1 is true, Statement 2 is true, Statement 2 is a correct explanation for Statement 3

B

Statement 1 is true, Statement 2 is true, Statement 2 is not a correct explanation for Statement 3

C

Statement 1 is true, Statement 2 is False

D

Statement 1 is False, Statement 2 is true

Text Solution

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To solve the given system of equations and analyze the statements, we will follow these steps: ### Step 1: Write the system of equations in matrix form The system of equations is: 1. \((a - 1)x - y - z = 0\) 2. \(x - (b - 1)y + z = 0\) 3. \(x + y - (c - 1)z = 0\) We can represent this system in matrix form as: \[ \begin{bmatrix} a - 1 & -1 & -1 \\ 1 & -(b - 1) & 1 \\ 1 & 1 & -(c - 1) \end{bmatrix} \begin{bmatrix} x \\ y \\ z \end{bmatrix} = \begin{bmatrix} 0 \\ 0 \\ 0 \end{bmatrix} \] ### Step 2: Set up the determinant For the system to have a non-trivial solution (i.e., not all \(x, y, z\) are zero), the determinant of the coefficient matrix must be zero: \[ \text{Det} = \begin{vmatrix} a - 1 & -1 & -1 \\ 1 & -(b - 1) & 1 \\ 1 & 1 & -(c - 1) \end{vmatrix} = 0 \] ### Step 3: Calculate the determinant We will calculate the determinant using cofactor expansion. Expanding along the first row: \[ \text{Det} = (a - 1) \begin{vmatrix} -(b - 1) & 1 \\ 1 & -(c - 1) \end{vmatrix} + 1 \begin{vmatrix} 1 & 1 \\ 1 & -(c - 1) \end{vmatrix} - 1 \begin{vmatrix} 1 & -(b - 1) \\ 1 & 1 \end{vmatrix} \] Calculating the 2x2 determinants: 1. \(\begin{vmatrix} -(b - 1) & 1 \\ 1 & -(c - 1) \end{vmatrix} = -(b - 1)(-(c - 1)) - 1 = (b - 1)(c - 1) - 1\) 2. \(\begin{vmatrix} 1 & 1 \\ 1 & -(c - 1) \end{vmatrix} = 1 \cdot (-(c - 1)) - 1 \cdot 1 = -(c - 1) - 1 = -c\) 3. \(\begin{vmatrix} 1 & -(b - 1) \\ 1 & 1 \end{vmatrix} = 1 \cdot 1 - 1 \cdot (-(b - 1)) = 1 + (b - 1) = b\) Putting it all together: \[ \text{Det} = (a - 1)((b - 1)(c - 1) - 1) - c - b \] ### Step 4: Set the determinant to zero Setting the determinant to zero gives: \[ (a - 1)((b - 1)(c - 1) - 1) - c - b = 0 \] ### Step 5: Rearranging the equation After simplifying the determinant equation, we get: \[ abc - ab - ac - bc + a + b + c - 1 = 0 \] This can be rearranged to: \[ ab + ac + bc = abc \] ### Step 6: Analyze Statement 1 From the above equation, we conclude that Statement 1 is true: - If \(x, y, z\) are not all zero, then \(ab + ac + bc = abc\). ### Step 7: Analyze Statement 2 Using the Arithmetic Mean-Geometric Mean (AM-GM) inequality: \[ \frac{ab + ac + bc}{3} \geq \sqrt[3]{(abc)^2} \] Given \(ab + ac + bc = abc\), we have: \[ \frac{abc}{3} \geq \sqrt[3]{(abc)^2} \] Cubing both sides leads to: \[ \frac{(abc)^3}{27} \geq (abc)^2 \] This implies: \[ abc \geq 27 \] Thus, Statement 2 is also true. ### Conclusion Both statements are true. Therefore, the final answer is: - **Both Statement 1 and Statement 2 are true.** ---

To solve the given system of equations and analyze the statements, we will follow these steps: ### Step 1: Write the system of equations in matrix form The system of equations is: 1. \((a - 1)x - y - z = 0\) 2. \(x - (b - 1)y + z = 0\) 3. \(x + y - (c - 1)z = 0\) ...
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