Question

$y=\int cos\left\{2ta{n}^{-1}\sqrt{\frac{1-x}{1+x}}\right\}dx$ is an equation of a family of

• A. straight lines
• B. circles
• C. ellipses
• D. parabolas

Answer 1

Answer: (D)

Putting $x=cos2\theta \therefore cos\left\{2ta{n}^{-1}\sqrt{\frac{1-x}{1+x}}\right\}=cos2\theta =x$
$\therefore y=\int xdx=\frac{x^2}{2}+c$