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If a,b,c are distinct real numbers and `|{:(a,a^(2),a^(3)-1),(b,b^(2),b^(3)-1),(c,c^(2),c^(3)-1):}|=0` then

A

`a+b+c=0`

B

`abc=1`

C

`a+b+c=1`

D

`ab+bc+ca=0`

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To solve the given problem, we need to evaluate the determinant: \[ D = \begin{vmatrix} a & a^2 & a^3 - 1 \\ b & b^2 & b^3 - 1 \\ c & c^2 & c^3 - 1 \end{vmatrix} \] and show that it equals zero under the condition that \(a\), \(b\), and \(c\) are distinct real numbers. ### Step 1: Write the Determinant We start with the determinant as given: \[ D = \begin{vmatrix} a & a^2 & a^3 - 1 \\ b & b^2 & b^3 - 1 \\ c & c^2 & c^3 - 1 \end{vmatrix} \] ### Step 2: Expand the Determinant We can expand the determinant using the properties of determinants. We can separate the last column: \[ D = \begin{vmatrix} a & a^2 & a^3 \\ b & b^2 & b^3 \\ c & c^2 & c^3 \end{vmatrix} - \begin{vmatrix} a & a^2 & 1 \\ b & b^2 & 1 \\ c & c^2 & 1 \end{vmatrix} \] ### Step 3: Evaluate the First Determinant The first determinant can be recognized as the Vandermonde determinant: \[ \begin{vmatrix} a & a^2 & a^3 \\ b & b^2 & b^3 \\ c & c^2 & c^3 \end{vmatrix} = (b-a)(c-a)(c-b) \] ### Step 4: Evaluate the Second Determinant The second determinant is also a Vandermonde determinant: \[ \begin{vmatrix} a & a^2 & 1 \\ b & b^2 & 1 \\ c & c^2 & 1 \end{vmatrix} = (b-a)(c-a)(c-b) \] ### Step 5: Combine the Results Combining the results from the two determinants, we have: \[ D = (b-a)(c-a)(c-b) - (b-a)(c-a)(c-b) \] This simplifies to: \[ D = 0 \] ### Conclusion Since the determinant \(D\) is equal to zero, we conclude that: \[ |{(a, a^2, a^3 - 1), (b, b^2, b^3 - 1), (c, c^2, c^3 - 1)}| = 0 \] This implies that the product of the factors must equal zero, leading us to the conclusion that \(abc = 1\). ### Final Result Thus, we find that: \[ abc = 1 \]
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