JEE Main & Advanced Mathematics Inverse Trigonometric Functions Question Bank Inverse trigonometric functions

  • question_answer
    \[{{\tan }^{-1}}\frac{{{c}_{1}}x-y}{{{c}_{1}}y+x}+{{\tan }^{-1}}\frac{{{c}_{2}}-{{c}_{1}}}{1+{{c}_{2}}{{c}_{1}}}+\]\[{{\tan }^{-1}}\frac{{{c}_{3}}-{{c}_{2}}}{1+{{c}_{3}}{{c}_{2}}}+...+{{\tan }^{-1}}\frac{1}{{{c}_{n}}}=\]

    A) \[{{\tan }^{-1}}\frac{y}{x}\]

    B) \[{{\tan }^{-1}}yx\]

    C) \[{{\tan }^{-1}}\frac{x}{y}\]

    D) \[{{\tan }^{-1}}(x-y)\]

    Correct Answer: C

    Solution :

      \[{{\tan }^{-1}}\left( \frac{{{c}_{1}}x-y}{{{c}_{1}}y+x} \right)+{{\tan }^{-1}}\left( \frac{{{c}_{2}}-{{c}_{1}}}{1+{{c}_{2}}{{c}_{1}}} \right)+{{\tan }^{-1}}\left( \frac{{{c}_{3}}-{{c}_{2}}}{1+{{c}_{3}}{{c}_{2}}} \right)+\]\[.....+{{\tan }^{-1}}\frac{1}{{{c}_{n}}}\]   = \[{{\tan }^{-1}}\left( \frac{\frac{x}{y}-\frac{1}{{{c}_{1}}}}{1+\frac{x}{y}.\frac{1}{{{c}_{1}}}} \right)+{{\tan }^{-1}}\left( \frac{\frac{1}{{{c}_{1}}}-\frac{1}{{{c}_{2}}}}{1+\frac{1}{{{c}_{1}}{{c}_{2}}}} \right)\]\[+{{\tan }^{-1}}\left( \frac{\frac{1}{{{c}_{2}}}-\frac{1}{{{c}_{3}}}}{1+\frac{1}{{{c}_{2}}{{c}_{3}}}} \right)+.......+{{\tan }^{-1}}\frac{1}{{{c}_{n}}}\] \[={{\tan }^{-1}}\frac{x}{y}-{{\tan }^{-1}}\frac{1}{{{c}_{1}}}+{{\tan }^{-1}}\frac{1}{{{c}_{1}}}-{{\tan }^{-1}}\frac{1}{{{c}_{2}}}+{{\tan }^{-1}}\frac{1}{{{c}_{2}}}\]\[-{{\tan }^{-1}}\frac{1}{{{c}_{3}}}+...+{{\tan }^{-1}}\frac{1}{{{c}_{n-1}}}-{{\tan }^{-1}}\frac{1}{{{c}_{n}}}+{{\tan }^{-1}}\frac{1}{{{c}_{n}}}\] =\[{{\tan }^{-1}}\left( \frac{x}{y} \right)\].


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