CET Karnataka Engineering CET - Karnataka Engineering Solved Paper-2000

  • question_answer
    General solution of tan \[5\theta =\cot 2\theta \] is:

    A)  \[\theta =\frac{n\pi }{7}+\frac{\pi }{14}\]            

    B)  \[\theta =\frac{n\pi }{7}+\frac{\pi }{5}\]

    C)  \[\theta =\frac{n\pi }{7}+\frac{\pi }{2}\]                              

    D)  \[\theta =\frac{n\pi }{7}+\frac{\pi }{3},n\in Z\]

    Correct Answer: A

    Solution :

    \[\tan 5\theta =\cot 2\theta \Rightarrow \tan 5\theta =\tan \left( \frac{\pi }{2}-2\theta  \right)\] therefore            \[5\theta =n\pi +\frac{\pi }{2}-2\theta \]                                 \[7\theta =n\pi +\frac{\pi }{2}\] \[\theta =\frac{n\pi }{7}+\frac{\pi }{14}\]


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