Q. If $I = \left| \int_{2}^{5}\frac{\sin{xdx}}{(1 + x^{2}} \right|,\ then$

A) $I \geq \frac{1}{4}$
B) $I\$lies in the interval $\left( \frac{1}{4},\frac{1}{5} \right)$
C) $I\$lies$\$in the interval $\left( \frac{1}{5},\frac{1}{6} \right)$
D) $I \leq \frac{3}{10}$
Explanation

(d)
Given, $I = \left| \int_{2}^{5}\frac{\sin{xdx}}{(1 + x^{2})} \right|$
$\leq \int_{2}^{5}{\left| \frac{\sin x}{1 + x^{2}} \right|dx}$
$\leq \int_{2}^{5}{\frac{1}{1 + x^{2}}dx \leq \int_{2}^{5}{\frac{1}{x^{2}}dx}}$
$= \left\lbrack \frac{x^{- 1}}{- 1} \right\rbrack_{2}^{5} = - \left\lbrack \frac{1}{5} - \frac{1}{2} \right\rbrack$
$\Rightarrow I \leq \frac{3}{10}$

Dr. Abubacker
Reviewed by Dr. Abubacker

Physics Educator & NEET/JEE Specialist

Ph.D. in Physics with 19+ years of teaching experience.

Want more practice?
Practice Integrals MCQs