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If f(x)=∣0x+ax+bx−a0x+cx−bx−c0∣f(x) = \begin{vmatrix} 0 & x+a & x+b \\ x-a & 0 & x+c \\ x-b & x-c & 0 \end{vmatrix} then the value of f(0)f(0) is equal to:

Solution

✅ Correct Option: 2

Putting x=0x=0 gives the matrix with rows (0,a,b)(0,a,b), (−a,0,c)(-a,0,c), (−b,−c,0)(-b,-c,0).

Here aij=−ajia_{ij}=-a_{ji} for every entry, so this is a skew-symmetric matrix of order 33.

The determinant of a skew-symmetric matrix of odd order is always 00, hence f(0)=0f(0)=0. Direct expansion confirms 0⋅(0+c2)−a(0+bc)+b(ac−0)=00\cdot(0+c^2)-a(0+bc)+b(ac-0)=0.

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