Let \( p = (x + y + z) \) and \( q = xyz \). If \( \begin{vmatrix} x & 1 & 1 \\ 1 & y & 1 \\ 1 & 1 & z \end{vmatrix} \) is positive, then which one of the following is correct ?

  1. A. q > p
  2. B. q + 1 > p
  3. C. q + 2 > p
  4. D. q + 2 \ge p

Correct Answer: C. q + 2 > p

Explanation

Expanding the determinant yields xyz - (x + y + z) + 2. Since this must be positive, we get q - p + 2 > 0, which means q + 2 > p.

Related questions on Matrices & Determinants

Practice more NDA Mathematics questions