Q. Let $f(x) = x - \lbrack x\rbrack$, for every real $x$, where [$x$]is the greatest integer less than or equal to $x$. Then, $\int_{- 1}^{1}{f(x)dx}\ is$

A) 1
B) 2
C) 3
D) 0
Explanation

(a)
$\int_{- 1}^{1}{\left( x - \lbrack x\rbrack \right)dx = \int_{- 1}^{0}{(x + 1)dx + \int_{0}^{1}{(x - 0)dx}}}$
$= \left\lbrack \frac{x^{2}}{2} + x \right\rbrack_{- 1}^{0} + \left\lbrack \frac{x^{2}}{2} \right\rbrack_{0}^{1} = \frac{1}{2} + \frac{1}{2} = 1$

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