Definite Integration Question 83

Question: $ \int _{-2}^{2}{| [x] |dx=} $

[EAMCET 2003]

Options:

A) 1

B) 2

C) 3

D) 4

Show Answer

Answer:

Correct Answer: D

Solution:

$ \int _{-2}^{2}{|[x]|}dx=\int _{-2}^{-1}{|[x]|dx+\int _{-1}^{0}{|[x]|dx+\int_0^{1}{|[x]|dx|+\int_1^{2}{|[x]|dx}}}} $

$ =\int _{-2}^{-1}{2dx}+\int _{-1}^{0}{1dx+\int_0^{1}{0dx+}}\int_1^{2}{1dx} $

$ =2[x] _{-2}^{-1}+[x] _{-1}^{0}+0+[x]_1^{2} $

$ =2(-1+2)+(0+1)+(2-1)=2+1+1=4. $