The area bounded by $$f\left( x \right) = {x^2},\,0 \leqslant x \leqslant 1,\,g\left( x \right) = - x + 2,\,1 \leqslant x \leqslant 2$$ and $$x$$-axis is :
A.
$$\frac{3}{2}$$
B.
$$\frac{4}{3}$$
C.
$$\frac{8}{3}$$
D.
None of these
Answer :
None of these
Solution :
Required area $$=$$ Area of $$OAB\,+$$ Area of $$ABC$$
Now, Area of $$OAB$$
$$\eqalign{
& = \int\limits_0^1 {f\left( x \right)dx} + \int\limits_1^2 {g\left( x \right)dx} \cr
& = \int\limits_0^1 {{x^2}dx} + \int\limits_1^2 {\left( { - x + 2} \right)dx} \cr
& = \left. {\frac{{{x^3}}}{3}} \right|_0^1 + \left[ {\frac{{ - {x^2}}}{2} + 2x} \right]_1^2 \cr
& = \frac{1}{3} + \left[ {\left( {\frac{{ - 4}}{2} + 4} \right) - \left( {\frac{{ - 1}}{2} + 2} \right)} \right] \cr
& = \frac{1}{3} + \frac{1}{2} \cr
& = \frac{5}{6}{\text{ sq}}{\text{. unit}} \cr} $$
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-