MCQ
$\int_0^{\pi /2} {\frac{{\cos x}}{{(1 + \sin x)(2 + \sin x)}}} \,dx = $
  • $\log \frac{4}{3}$
  • B
    $\log \frac{1}{3}$
  • C
    $\log \frac{3}{4}$
  • D
    None of these

Answer

Correct option: A.
$\log \frac{4}{3}$
a
(a) Put $\sin x = t \Rightarrow \cos x\,dx = dt,$

so that reduced integral is 

$\int_0^1 {\left( {\frac{1}{{1 + t}} - \frac{1}{{2 + t}}} \right)\,\,dt = [\log (1 + t) - \log (2 + t)]_0^1} $

$ = \log \frac{2}{3} - \log \frac{1}{2} = \log \frac{4}{3}$.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Let $M$  and  $m$  be respectively the local maximum and the local minimum values of the function, $f(x) = \,2{x^3} - 9{x^2} + 12x + 5$  in the interval $[0, 3].$  Then $M-m$  is equal to
The adjoint of $\left[ {\begin{array}{*{20}{c}}1&1&1\\1&2&{ - 3}\\2&{ - 1}&3\end{array}} \right]$is
If the diraction ratios of a line are proportional to $1, -3, 2,$ then its diraction cosines are:
The position vector of a point at a distance of $3\sqrt {11} $ units from $i - j + 2k$ on a line passing through the points $i - j + 2k$ and $3i + j + k$ is
Let $f(x) = x^2$ and $g(x) = 2^x$. Then, the solution set of the equation $\text{fog(x) = gof(x)}$ is:
$Q^+$ denote the set of all positive rational numbers. If the binary operation $\text{a }\odot$ on $Q^+$ is defined as: $\text{a }\odot=\frac{\text{ab}}{2}$, then the inverse of $3$ is:
The relation $'R\ '$ in $N \times N$ such that $(a, b)R(c, d) \Leftrightarrow a + d = b + c$ is:
Two sides of a triangle are to have lengths $'a'$ cm & $'b'$ cm. If the triangle is to have the maximum area, then the length of the median from the vertex containing the sides $'a'$ and $'b'$ is
If the random variable $X$ has the following distribution :
$X:$ $0$ $1$ $2$ $3$ $4$ $5$ $6$ $7$ $8$
$P(X):$ $a$ $3a$ $5a$ $7a$ $9a$ $11a$ $13a$ $15a$ $17a$
then the value of a is :
If $\begin{bmatrix}2&\text{amp; }3\\4&\text{amp; }4\end{bmatrix}+\begin{bmatrix}\text{x}&\text{amp; }3\\\text{y}&\text{amp; }1\end{bmatrix}=\begin{bmatrix}10&\text{amp; }6\\8&\text{amp; }5\end{bmatrix}$ then $(\text{x, y})=$