A) \[\frac{-1}{2}\]
B) \[\frac{1}{2}\]
C) \[2\]
D) \[-2\]
Correct Answer: D
Solution :
Direction ratio of line \[{{L}_{1}}\] is \[\left| \begin{matrix} {\hat{i}} & {\hat{j}} & {\hat{k}} \\ 1 & -2 & 4 \\ 2 & 1 & 1 \\ \end{matrix} \right|\] \[=-6\hat{i}+7\hat{j}+5\hat{k}\] \[\therefore \,\,{{L}_{1}}\bot {{L}_{2}}\Rightarrow \,2(-6)\,+7(1)\,+2a(5)=0\] \[\Rightarrow \,\,a=\frac{1}{2}\]You need to login to perform this action.
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