Trigonometry · JEE Main previous year questions

2015 1 question

1. Q82015 · 4 Apr 2015 · Shift 1

   Let ${\tan }^{-1}y={\tan }^{-1}x+{\tan }^{-1}\left(\frac{2x}{1-x^2}\right)$, where $|x|<\frac{1}{\sqrt{3}}$. Then a value of $y$ is :

   1. A.$\frac{3x-x^3}{1+3x^2}$
   2. B.$\frac{3x+x^3}{1+3x^2}$
   3. C.$\frac{3x-x^3}{1-3x^2}$
   4. D.$\frac{3x+x^3}{1-3x^2}$
   Show answer

   Answer: C