2. Sample Papers
  3. JEE Main & Advanced

JEE Main & Advanced Sample Paper JEE Main Sample Paper-33

  • question_answer
    Let \[A=\left[ _{0}^{\sin \theta }\,\,_{-\sin \theta }^{0} \right]\]. If \[A\text{ + }{{A}^{T}}\] is a null matrix,  then the number of values of \[\theta \] in (0, 6), is

    A)  4        

    B)                                     3

    C)  2          

    D)                                     1

    Correct Answer: D

    Solution :

    \[A+{{A}^{T}}=O\Rightarrow \,\left[ \begin{matrix}    2\,\sin \,\theta   \\    0  \\ \end{matrix}\,\,\begin{matrix}    0  \\    -2\,\sin \,\theta   \\ \end{matrix} \right]=O\] \[\Rightarrow \,\sin \,\theta \,=0\,\Rightarrow \,\theta =\,n\pi ,\,\,n\,\in \,I\] \[\therefore \,\,\theta \,=\pi \,\in \,(0,6)\]


You need to login to perform this action.
You will be redirected in 3 sec spinner