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Given that the system of equations x...

Given that the system of equations `x=cy+bz ,y=az+cx , z=bx +ay` has nonzero solutions and and at least one of the a,b,c is a proper fraction.
`a^(2)+b^(2)+c^(2)` is

A

` gt 2`

B

`gt 3`

C

`lt 3`

D

`lt2`

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To solve the given system of equations and find the value of \( a^2 + b^2 + c^2 \), we will follow these steps: ### Step 1: Write the system of equations in standard form The given equations are: 1. \( x = cy + bz \) 2. \( y = az + cx \) 3. \( z = bx + ay \) Rearranging them gives: 1. \( x - cy - bz = 0 \) 2. \( -cx + y - az = 0 \) 3. \( -bx - ay + z = 0 \) ### Step 2: Set up the coefficient matrix From the rearranged equations, we can form the coefficient matrix \( A \): \[ A = \begin{pmatrix} 1 & -c & -b \\ -c & 1 & -a \\ -b & -a & 1 \end{pmatrix} \] ### Step 3: Find the determinant of the matrix For the system to have non-zero solutions, the determinant of the matrix must be zero: \[ \text{det}(A) = 0 \] Calculating the determinant: \[ \text{det}(A) = 1 \cdot \begin{vmatrix} 1 & -a \\ -a & 1 \end{vmatrix} - (-c) \cdot \begin{vmatrix} -c & -a \\ -b & 1 \end{vmatrix} - (-b) \cdot \begin{vmatrix} -c & 1 \\ -b & -a \end{vmatrix} \] Calculating the 2x2 determinants: 1. \( \begin{vmatrix} 1 & -a \\ -a & 1 \end{vmatrix} = 1 - a^2 \) 2. \( \begin{vmatrix} -c & -a \\ -b & 1 \end{vmatrix} = -c + ab \) 3. \( \begin{vmatrix} -c & 1 \\ -b & -a \end{vmatrix} = ac - b \) Substituting back: \[ \text{det}(A) = 1(1 - a^2) + c(c - ab) + b(ac - b) \] Expanding this gives: \[ \text{det}(A) = 1 - a^2 + c^2 - abc + acb - b^2 = 1 - a^2 - b^2 - c^2 + 2abc \] Setting the determinant to zero: \[ 1 - a^2 - b^2 - c^2 + 2abc = 0 \] Thus, we have: \[ a^2 + b^2 + c^2 + 2abc = 1 \] ### Step 4: Analyze the conditions Given that at least one of \( a, b, c \) is a proper fraction, we know: - \( 1 - a^2 > 0 \) - \( 1 - b^2 > 0 \) - \( 1 - c^2 > 0 \) This implies: \[ a^2 < 1, \quad b^2 < 1, \quad c^2 < 1 \] ### Step 5: Sum the inequalities Adding these inequalities: \[ (1 - a^2) + (1 - b^2) + (1 - c^2) > 0 \implies 3 - (a^2 + b^2 + c^2) > 0 \] Thus: \[ a^2 + b^2 + c^2 < 3 \] ### Conclusion The value of \( a^2 + b^2 + c^2 \) is less than 3.

To solve the given system of equations and find the value of \( a^2 + b^2 + c^2 \), we will follow these steps: ### Step 1: Write the system of equations in standard form The given equations are: 1. \( x = cy + bz \) 2. \( y = az + cx \) 3. \( z = bx + ay \) ...
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