MCQ
The value of $\int_0^1 {\frac{{dx}}{{{e^x} + {e^{ - x}}}}} $ is
  • A
    ${\tan ^{ - 1}}\left( {\frac{{1 - e}}{{1 + e}}} \right)$
  • ${\tan ^{ - 1}}\left( {\frac{{e - 1}}{{e + 1}}} \right)$
  • C
    $\frac{\pi }{4}$
  • D
    ${\tan ^{ - 1}}e + \frac{\pi }{4}$

Answer

Correct option: B.
${\tan ^{ - 1}}\left( {\frac{{e - 1}}{{e + 1}}} \right)$
b
(b) $\int_0^1 {\frac{{dx}}{{{e^x} + {e^{ - x}}}} = \int_0^1 {\frac{{{e^x}}}{{1 + {e^{2x}}}}dx} } $

Now put ${e^x} = t \Rightarrow {e^x}dx = dt$

Also as $x = 0$ to $1$, $t = 1$ to $e$, then reduced form is

$\int_1^e {\frac{{dt}}{{1 + {t^2}}} = [{{\tan }^{ - 1}}t]_1^e} = {\tan ^{ - 1}}\left( {\frac{{e - 1}}{{e + 1}}} \right)$,  

$\left[ \because {{\tan }^{-1}}x-{{\tan }^{-1}}y={{\tan }^{-1}}\left( \frac{x-y}{1+xy} \right) \right]$.

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 $S$ be the set of all $\alpha  \in  R$ such that the equation, $cos\,2 x + \alpha  \,sin\, x = 2\alpha  -7$ has a solution. Then $S$ is equal to
A triangular corner is cut from a rectangular piece of paper and the resulting pentagon has sides $5,6,8,9, 12$ in some order. The ratio of the area of the pentagon to the area of the rectangle is
Integral curve satisfying $y' = \frac{{{x^2} + {y^2}}}{{{x^2} - {y^2}}},\;y(1) = 2$ has the slope at the point $(1, 0)$ of the curve, equal to
Period of $|2\sin 3\theta + 4\cos 3\theta |$ is
$\int_{}^{} {\sqrt {1 + \cos x} \;dx} $ equals
The function $f(x) =$ $\sqrt {1 - \sqrt {1 - {x^2}} } $
Consider the equation $\int_1^e \frac{\left(\log _e x \right)^{1 / 2}}{ x \left(a-\left(\log _{ e } x \right)^{3 / 2}\right)^2} dx =1, \quad a \in(-\infty, 0) \cup(1, \infty)$.

Which of the following statements is/are $TRUE$ ?

$(A)$ No $a$ satisfies the above equation

$(B)$ An integer $a$ satisfies the above equation

$(C)$ An irrational number $a$ satisfies the above equation

$(D)$ More than one $a$ satisfy the above equation

Set of equations $a + b - 2c = 0,$ $2a - 3b + c = 0$ and $a - 5b + 4c = \alpha $ is consistent for $\alpha$ equal to
If ${\Delta _1} = \left| {\,\begin{array}{*{20}{c}}1&0\\a&b\end{array}\,} \right|$ and ${\Delta _2} = \left| {\begin{array}{*{20}{c}}1&0\\c&d\end{array}} \right|$, then ${\Delta _2}{\Delta _1}$is equal to
If $\alpha $and $\beta $ are roots of the equation $A{x^2} + Bx + C = 0$, then value of ${\alpha ^3} + {\beta ^3}$ is