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STD 12 - 3 and 4 . determinant and metrices — JEE STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceJEESTD 12 - 3 and 4 . determinant and metrices4 Marks
Question
If ${2^{{a_1}}},{2^{{a_2}}},{2^{{a_3}}},{......2^{{a_n}}}$ are in $G.P.$ then $\left| {\begin{array}{*{20}{c}}
  {{a_1}}&{{a_2}}&{{a_3}} \\ 
  {{a_{n + 1}}}&{{a_{n + 2}}}&{{a_{n + 3}}} \\ 
  {{a_{2n + 1}}}&{{a_{2n + 2}}}&{{a_{2n + 3}}} 
\end{array}} \right|$ is equal to
✓

Answer

c
$a_{1}, a_{2}, a_{3}$ are in $A . P$

so $\quad {{\rm{R}}_2} \to {{\rm{R}}_2} - \left( {\frac{{{{\rm{R}}_1} + {{\rm{R}}_3}}}{2}} \right)$

$ \Rightarrow \boxed{\Delta  = 0}$

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