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if x ne 0 , y ne 0 ,z ne 0 " and " |{...

if `x ne 0 , y ne 0 ,z ne 0 " and " |{:(1+x,,1,,1),(1+y,,1+2y,,1),(1+z,,1+z,,1+3z):}|=0` then
`x^(-1) +y^(-1) +z^(-1)` is equal to

A

`-1`

B

`-2`

C

`-3`

D

none of these

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The correct Answer is:
To solve the given problem, we need to evaluate the determinant and find the value of \( \frac{1}{x} + \frac{1}{y} + \frac{1}{z} \). Given the determinant: \[ D = \begin{vmatrix} 1 + x & 1 & 1 \\ 1 + y & 1 + 2y & 1 \\ 1 + z & 1 + z & 1 + 3z \end{vmatrix} \] We know that \( |D| = 0 \). ### Step 1: Factor out \( xyz \) First, we can factor out \( xyz \) from the determinant. We rewrite the determinant as follows: \[ D = xyz \begin{vmatrix} \frac{1}{x} + 1 & 1 & 1 \\ \frac{1}{y} + 1 & \frac{1 + 2y}{y} & 1 \\ \frac{1}{z} + 1 & \frac{1 + z}{z} & \frac{1 + 3z}{z} \end{vmatrix} \] This simplifies to: \[ D = xyz \begin{vmatrix} 1 + \frac{1}{x} & 1 & 1 \\ 1 + \frac{1}{y} & 1 + 2 & 1 \\ 1 + \frac{1}{z} & 1 + 1 & 1 + 3 \end{vmatrix} \] ### Step 2: Row operations Now, we perform row operations to simplify the determinant. We can add the rows together: \[ R_1 \rightarrow R_1 + R_2 + R_3 \] This gives us: \[ D = xyz \begin{vmatrix} 3 + \frac{1}{x} + \frac{1}{y} + \frac{1}{z} & 1 & 1 \\ 1 + \frac{1}{y} & 1 + 2 & 1 \\ 1 + \frac{1}{z} & 1 + 1 & 1 + 3 \end{vmatrix} \] ### Step 3: Expand the determinant Now we can expand the determinant. The determinant is set to zero: \[ xyz \left(3 + \frac{1}{x} + \frac{1}{y} + \frac{1}{z}\right) = 0 \] ### Step 4: Analyze the equation Since \( x, y, z \neq 0 \), we know that \( xyz \neq 0 \). Therefore, we can conclude: \[ 3 + \frac{1}{x} + \frac{1}{y} + \frac{1}{z} = 0 \] ### Step 5: Solve for \( \frac{1}{x} + \frac{1}{y} + \frac{1}{z} \) Rearranging the equation gives us: \[ \frac{1}{x} + \frac{1}{y} + \frac{1}{z} = -3 \] Thus, the final answer is: \[ \frac{1}{x} + \frac{1}{y} + \frac{1}{z} = -3 \]

To solve the given problem, we need to evaluate the determinant and find the value of \( \frac{1}{x} + \frac{1}{y} + \frac{1}{z} \). Given the determinant: \[ D = \begin{vmatrix} 1 + x & 1 & 1 \\ 1 + y & 1 + 2y & 1 \\ 1 + z & 1 + z & 1 + 3z ...
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