The area bounded by the curves $$y = \ell n\,x,\,y = \ell n\left| x \right|,\,y = \left| {\ell n\,x} \right|$$ and $$y = \left| {\ell n\left| x \right|} \right|$$ is :
A.
4 sq. units
B.
6 sq. units
C.
10 sq. units
D.
None of these
Answer :
4 sq. units
Solution :
First we draw each curve as separate graph
Clearly the bounded area is as shown in the following figure.
Required area
$$\eqalign{
& = 4\int\limits_0^1 {\left( { - \ell n\,x} \right)} dx \cr
& = - 4\left[ {x\,\ell n\,x - x} \right]_0^1 \cr
& = 4{\text{ sq}}{\text{. units}} \cr} $$
Releted MCQ Question on Calculus >> Application of Integration
Releted Question 1
The area bounded by the curves $$y = f\left( x \right),$$ the $$x$$-axis and the ordinates $$x = 1$$ and $$x = b$$ is $$\left( {b - 1} \right)\sin \left( {3b + 4} \right).$$ Then $$f\left( x \right)$$ is-