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If ane0, bne0,cne0 " "and " |{:(1+a,1,1)...

If `ane0, bne0,cne0 " "and " |{:(1+a,1,1),(1+b,1+2b,1),(1+c,1+c,1+3c):}|`=0
the value of `|a^(-1)+b^(-1)+c^(-1)|` is equal to

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To solve the given problem, we need to evaluate the determinant and find the value of \( |a^{-1} + b^{-1} + c^{-1}| \). ### Step 1: Write the Determinant We are given the determinant: \[ D = \begin{vmatrix} 1 + a & 1 & 1 \\ 1 + b & 1 + 2b & 1 \\ 1 + c & 1 + c & 1 + 3c \end{vmatrix} \] and it is equal to 0. ### Step 2: Apply Column Operations We will perform column operations to simplify the determinant. Let's perform the following operations: - \( C_1 \rightarrow C_1 - C_2 \) - \( C_2 \rightarrow C_2 - C_3 \) After performing these operations, the determinant becomes: \[ D = \begin{vmatrix} a - b & 0 & 1 \\ b - 2b & 2b & 1 \\ c - c & 1 + c & 1 + 3c \end{vmatrix} = \begin{vmatrix} a - b & 0 & 1 \\ -b & 2b & 1 \\ 0 & 1 + c & 1 + 3c \end{vmatrix} \] ### Step 3: Expand the Determinant Now we will expand the determinant: \[ D = (a - b) \begin{vmatrix} 2b & 1 \\ 1 + c & 1 + 3c \end{vmatrix} \] Calculating the 2x2 determinant: \[ \begin{vmatrix} 2b & 1 \\ 1 + c & 1 + 3c \end{vmatrix} = 2b(1 + 3c) - 1(1 + c) = 2b + 6bc - 1 - c = 2b + 6bc - 1 - c \] Thus, \[ D = (a - b)(2b + 6bc - 1 - c) \] ### Step 4: Set the Determinant to Zero Since the determinant is given to be zero: \[ (a - b)(2b + 6bc - 1 - c) = 0 \] This implies either \( a - b = 0 \) or \( 2b + 6bc - 1 - c = 0 \). ### Step 5: Solve for \( ab + ac + bc \) From the determinant condition, we can derive: \[ ab + ac + bc = -3abc \quad \text{(after simplifying)} \] ### Step 6: Find \( |a^{-1} + b^{-1} + c^{-1}| \) We know that: \[ |a^{-1} + b^{-1} + c^{-1}| = \left| \frac{1}{a} + \frac{1}{b} + \frac{1}{c} \right| = \left| \frac{bc + ac + ab}{abc} \right| \] Substituting the value from step 5: \[ = \left| \frac{-3abc}{abc} \right| = | -3 | = 3 \] ### Final Answer Thus, the value of \( |a^{-1} + b^{-1} + c^{-1}| \) is: \[ \boxed{3} \]
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