12th Class Mathematics Applications of Derivatives Question Bank Case Based (MCQs) - Derivatives

  • question_answer
    \[\sqrt{\frac{1-\cos x}{1+\cos \,x}}\]

    A) \[\frac{1}{2}{{\sec }^{2}}\frac{x}{2}\]

    B) \[-\frac{1}{2}{{\sec }^{2}}\frac{x}{2}\]

    C) \[{{\sec }^{2}}\frac{x}{2}\]

    D) \[-{{\sec }^{2}}\frac{x}{2}\]

    Correct Answer: A

    Solution :

    Let \[y=\frac{\sqrt{1-\cos \,x}}{\sqrt{1+\cos \,x}}=\sqrt{\frac{1-1+2{{\sin }^{2}}\frac{x}{2}}{2{{\cos }^{2}}\frac{x}{2}-1+1}}=\tan \left( \frac{x}{2} \right)\] \[\therefore \,\,\frac{dy}{dx}={{\sec }^{2}}\frac{x}{2}.\frac{1}{2}=\frac{1}{2}{{\sec }^{2}}\frac{x}{2}\]


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