MCQ
$\int_{\,\pi }^{\,10\pi } {\,|\sin x|dx} $ is
  • A
    $20$
  • B
    $8$
  • C
    $10$
  • $18$

Answer

Correct option: D.
$18$
d
(d) $\int_\pi ^{10\pi } {|\sin x|dx = \int_0^\pi {|\sin x|dx + \int_\pi ^{10\pi } {\,\,|\sin x|dx} } } - \int_0^\pi {\,|\sin x|dx} $

$ = \int_0^{10\pi } {|\sin x|dx - \int_0^\pi {\,|\sin x|dx} } $

$ = 10\int_{\,0}^{\,\pi } {|\sin x|dx - \int_{\,0}^{\,\pi } {\,|\sin x|dx} } $

$ = 9\int_{\,0}^{\,\pi } {\sin x\,dx} $

$[\because \,|\sin x|$ is periodic with period $\pi $ and in $[0,\pi ],\sin x \ge 0]$

$ = 9\,[ - \cos x]_0^\pi = 9\,( - \cos \pi + \cos 0)$

$ = 9\,(1 + 1) = 18$.

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

Choose the correct answer in each of the following:
If A and B are any two events such that P(A) + P(B) – P(A and B) = P(A), then
Two squares are chosen at random on a chess-board. The probability that they have a side in common, is
$A$ and $B$ are two students. Their chances of solving a problem correctly are $\frac{1}{3}$ and $\frac{1}{4}$ respectively. If the probability of their making common error is $\frac{1}{20}$ and they obtain the same answer, then the probability of their answer to be correct is.
If $\text{A}=\displaystyle \left[ \begin{matrix} 1 &\text{amp; 2} \\ 3&\text{amp; 4} \end{matrix} \right],$ then which of the following is not an element of $A ?$
$ \sin ^{ -1 } \frac { 3 }{ 5 } +\sin^{ -1 }\frac { 4 }{ 5 }$ is equal to
If $A$ and $B$ are square matrices such that $B=-A^{-1} B A,$ then $(A+B)^2=$
Let $\text{X}=\begin{bmatrix}\text{x}_1\\\text{x}_2\\\text{x}_3\end{bmatrix},\text{A}=\begin{bmatrix}1&-1&2\\2&0&1\\3&2&1\end{bmatrix}$ and $\text{B}=\begin{bmatrix}3\\1\\4\end{bmatrix}$. If $AX = B,$ then $X$ is equal to:
If the minimum value of an objective function $Z=a x+b y$ occurs at two points $(3,4)$ and $(4,3)$ then
A curve $y = f (x)$ passing through the point $\left( {1,\,\,\frac{1}{{\sqrt e }}} \right)$ satisfies the differential equation $\frac{{dy}}{{dx}} + x\,{e^{ - \;\frac{{{x^2}}}{2}}} =0.$ Then which of the following does not hold good?
If $\omega $is a cube root of unity, then $\left| {\,\begin{array}{*{20}{c}}{x + 1}&\omega &{{\omega ^2}}\\\omega &{x + {\omega ^2}}&1\\{{\omega ^2}}&1&{x + \omega }\end{array}\,} \right| = $