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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
If $A = \left[ {\begin{array}{*{20}{c}}3&5\\2&0\end{array}} \right]$ and $B = \left[ {\begin{array}{*{20}{c}}1&{17}\\0&{ - 10}\end{array}} \right]$ then $|AB|$ is equal to
  • A
    $80$
  • ✓
    $100$
  • C
    $-110$
  • D
    $92$
✓

Answer

Correct option: B.
$100$
b
(b) Since $A$ and $ B $ are square matrix 

$\therefore $$|AB|\, = |A||B|$; $|A|\, = - 10;|B| = - 10$

$\therefore $$|AB|\, = 100$.

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