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The value of ∣abcbcacab∣\begin{vmatrix} a & b & c \\ b & c & a \\ c & a & b \end{vmatrix} is negative, if

Solution

✅ Correct Option: 1

Expanding gives −(a3+b3+c3−3abc)=−(a+b+c)(a2+b2+c2−ab−bc−ca)-(a^3+b^3+c^3-3abc)=-(a+b+c)(a^2+b^2+c^2-ab-bc-ca). For distinct positive a,b,ca,b,c the first factor is positive and the second, being half the sum of squared differences, is also positive, so the determinant is negative.

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