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 25.

Answers (1)

Answer:

\frac{8 \pi}{3}\; \text{sq. units}

Hint: :

\int \sqrt{a^{2}-x^{2}} d x=\frac{x}{2} \sqrt{a^{2}-x^{2}}+\frac{a^{2}}{2} \sin -\frac{1}{a}+c \text {. } .

Given:

The given equations are x^2+y^2=16  and y=\sqrt{3}x .

Solution:

x^2+y^2=16   Represents a circle with centreo(0,0) and cutting the x axis at A(4,0)

 y=\sqrt{3}x  Represents straight passing through o(0,0) .

Point of intersection  is obtained by solving the two equations.

x^2+y^2=16 and y=\sqrt{3}x 

x^{2}+(\sqrt{3} x)^{2} =16

4x^2=16

x=\pm 2

y=\pm 2\sqrt{3}

B(2,2\sqrt{3}) and B'(-2,-2\sqrt{3}) are points of intersection of circle and straight line

Shaded area (OBQAO) =area(OBPO)+area(PBQAP)

 

\begin{aligned} &=\int_{0}^{2} \sqrt{3} x d x+\int_{2}^{4} \sqrt{16-x^{2}} d x \\ &=\sqrt{3}\left[\frac{x^{2}}{2}\right]_{0}^{2}+\left[\frac{1}{2} x \sqrt{16-x^{2}}+\frac{16}{2} \sin ^{-1}\left(\frac{x}{4}\right)_{2}^{4}\right] \\ &=2 \sqrt{3}+8 \frac{\pi}{2}-2 \sqrt{3}-8 \frac{\pi}{6} \\ &=2 \sqrt{3}+4 \pi-2 \sqrt{3}-\frac{4 \pi}{3} \\ &=\frac{8 \pi}{3} \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