Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Definite Integration

Question:

$\int\limits^{\frac{\pi}{3}}_{0}\frac{sinx}{(2-cosx)^2}dx=$

Options:

$\frac{1}{2}$

1

$\frac{2}{3}$

$\frac{1}{3}$

Correct Answer:

$\frac{1}{3}$

Explanation:

The correct answer is Option (4) → $\frac{1}{3}$

$\int\limits^{\frac{\pi}{3}}_{0}\frac{\sin x}{(2-\cos x)^2}dx$

Let $y=2-\cos x$

$dy=\sin xdx$

as $x→0,y→1$

$x→\frac{π}{3},y→\frac{3}{2}$

$I=\int\limits^{\frac{3}{2}}_{1}\frac{dy}{y^2}$

$=\left[\frac{-1}{y}\right]^{\frac{3}{2}}_{1}=1-\frac{2}{3}=\frac{1}{3}$