question_answer

The equation of the plane containing the lines \[\vec{r}={{\vec{a}}_{1}}+\lambda \,{{\vec{a}}_{2}}\] and \[\vec{r}={{\vec{a}}_{2}}+\lambda \,{{\vec{a}}_{1}}\] is

A) \[[\vec{r}\,\,{{\vec{a}}_{1}}\,{{\vec{a}}_{2}}]=0\]      

B)  \[[\vec{r}\,\,{{\vec{a}}_{2}}\,{{\vec{a}}_{1}}]={{\vec{a}}_{1}}.{{\vec{a}}_{2}}\]

C)  \[[\vec{r}\,\,{{\vec{a}}_{2}}\,{{\vec{a}}_{1}}]={{\vec{a}}_{1}}.{{\vec{a}}_{2}}\]

D)         None of these