Get Answers to all your Questions

header-bg qa

Need solution for RD Sharma Maths Class 12 Chapter 20 Areas of Bounded Regions exercise 20.3 question 29.

Answers (1)

Answer:

\frac{9}{2}\text{sq. units}

Hint:

 Use concept.

Given:

The given equations are y=2-x^2 and  y+x=0 .

Solution:

 To find area bounded by

y=2-x^2            ......(1)

y+x=0        .......(2)

Equation (1) represents  a parabola with vertex (0,2)  and downward, meets axes at (\pm 0, \sqrt{2}) .

Equation (2) represents a line passing through (0,0)   and (2,-2) .The points of intersection of line  and parabola are  (2,-2)  and (1,-1) .

A rough sketch of curve is as follows:

Shaded region is sliced into rectangles with area =(y_2-y_1)_{\Delta }x. It slides from x =-1  to x = 2 so,

Required area =Region ABPCOA

\begin{aligned} &A=\int_{-1}^{2}\left(y_{1}-y_{2}\right) d x \\ &=\int_{-1}^{2}\left(2-x^{2}+x\right) d x \\ &=\left[2 x-\frac{x^{3}}{3}+\frac{x^{2}}{2}\right]_{-1}^{2} \\ &=\left[\left(4-\frac{8}{3}+2\right)-\left(-2+\frac{1}{3}+\frac{1}{2}\right)\right] \\ &=\left[\frac{10}{3}+\frac{7}{6}\right] \\ &=\frac{27}{6} \\ &=\frac{9}{2} \text { sq.units } \end{aligned}

Posted by

infoexpert24

View full answer

Crack CUET with india's "Best Teachers"

  • HD Video Lectures
  • Unlimited Mock Tests
  • Faculty Support
cuet_ads