MCQ
If $\Delta = \left| {\,\begin{array}{*{20}{c}}a&b&c\\x&y&z\\p&q&r\end{array}\,} \right|$, then $\left| {\,\begin{array}{*{20}{c}}{ka}&{kb}&{kc}\\{kx}&{ky}&{kz}\\{kp}&{kq}&{kr}\end{array}\,} \right|$=
  • A
    $\Delta $
  • B
    $k\Delta $
  • C
    $3k\Delta $
  • ${k^3}\Delta $

Answer

Correct option: D.
${k^3}\Delta $
d
(d)$\left| {\,\begin{array}{*{20}{c}}{ka}&{kb}&{kc}\\{kx}&{ky}&{kz}\\{kp}&{kq}&{kr}\end{array}\,} \right|\, = \,{k^3}\,\left| {\,\begin{array}{*{20}{c}}a&b&c\\x&y&z\\p&q&r\end{array}\,} \right| = {k^3}\Delta $.

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