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3 and 4 . determinant and metrices — Maths STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceMaths3 and 4 . determinant and metrices1 Mark
MCQ
$\left| {\,\begin{array}{*{20}{c}}{1/a}&1&{bc}\\{1/b}&1&{ca}\\{1/c}&1&{ab}\end{array}\,} \right| = $
  • ✓
    $0$
  • B
    $abc$
  • C
    $1/abc$
  • D
    None of these
✓

Answer

Correct option: A.
$0$
a
(a) $\Delta = \frac{1}{a}[ab - ca] + 1\left[ {ca.\frac{1}{c} - \frac{1}{b}.ab} \right] + bc\left[ {\frac{1}{b} - \frac{1}{c}} \right]$

==>$\Delta = (b - c) + 1(a - a) + (c - b)$

==> $\Delta = 0$.

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