A) n
B) n-1
C) n+1
D) none of these
Correct Answer: C
Solution :
[c] Taking \[{{x}^{5}}\]common from last row, we get \[{{x}^{5}}\left| \begin{matrix} {{x}^{n}} & {{x}^{n+2}} & {{x}^{2n}} \\ 1 & {{x}^{a}} & a \\ {{x}^{n}} & {{x}^{a+1}} & {{x}^{2n}} \\ \end{matrix} \right|=0,\forall x\in R\] \[\Rightarrow a+1=n+2\] or \[a=n+1\] (as it will make first and third row is identical)
You need to login to perform this action.
You will be redirected in
3 sec
