WB JEE Medical WB JEE Medical Solved Paper-2008

  • question_answer
    The angle subtended by the vector \[A=4\hat{i}+3\hat{j}+12\hat{k}\]with the \[x-\]axis is

    A)  \[{{\sin }^{-1}}\left( \frac{3}{13} \right)\]                            

    B)  \[{{\sin }^{-1}}\left( \frac{4}{13} \right)\]

    C)  \[{{\cos }^{-1}}\left( \frac{4}{13} \right)\]                           

    D)  \[{{\cos }^{-1}}\left( \frac{3}{13} \right)\]

    Correct Answer: C

    Solution :

                     The angle subtended by the vector \[\text{\vec{A}}\]with the x-axis is \[\cos \theta =\frac{4}{\sqrt{{{4}^{2}}+{{3}^{2}}+{{(12)}^{2}}}}=\frac{4}{13};\] \[\cos \theta ={{\cos }^{-1}}\left( \frac{4}{13} \right)\]


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