Browse by Stream
QnA
Home
QnA
Go To Your Study Dashboard

Get Answers to all your Questions

header-bg qa
  • Home
  • School
  • Need solution for RD Sharma maths class 12 chapter 20 Areas of Bounded Regions exercise multiple choice question 39

Need solution for RD Sharma maths class 12 chapter 20 Areas of Bounded Regions exercise multiple choice question 39

Answers (1)

Answer:

 (d)

Hint:

 Find the intersection point

Given:

 \begin{aligned} &x^{2}=4y\\ &x=4y-2 \qquad \qquad \qquad \dots (i) \end{aligned}

Explanation:

Intersection points are

\begin{aligned} &x^{2}=4y\\ &(4y-2)^{2}=4y\\ &16y^{2}+4-16y=4y\\ &16y^{2}-20y+4=0\\ &4y^{2}-5y+1=0\\ &4y^{2}-4y-y+1=0\\ &4y(y-1)-1(y-1)=0\\ &(y-1)(4y-1)=0\\ &y=1, y=\frac{1}{4} \\ &y=1\Rightarrow x=2\\ &y=\frac{1}{4}\Rightarrow x=4\left ( \frac{1}{4}\right )-2=-1 \qquad \text {[From (i)]}\end{aligned}

Area

\begin{aligned} &=\int_{-1}^{2}\left [ \left ( \frac{x+2}{4} \right )-\frac{x^{2}}{4} \right ]dx\\ &=\left [ \frac{x^{2}}{8}+\frac{2x}{4}-\frac{x^{2}}{12} \right ]_{-1}^{2}\\ &=\frac{1}{4}\left [ \left ( 2+4-\frac{8}{3} \right )-\left ( \frac{1}{2}-2+\frac{1}{3} \right ) \right ]\\ &=\frac{1}{4}\left [ \frac{10}{3}-\left ( \frac{-7}{6} \right ) \right ]\\ &=\frac{1}{4}\left ( \frac{9}{2} \right )\\ &=\frac{9}{8} \text { sq.units } \end{aligned}

Posted by

Gurleen Kaur

View full answer

Crack CUET with india's "Best Teachers"

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

Similar Questions

Trending Articles/News

anam-khan

CBSE 12th Result 2026: Board refutes OSM glitch claims, says Class 12 results likely in third week of May
anam-khan

CBSE 12th Result 2026 LIVE: Class 12 results soon at cbse.gov.in, direct link, digilocker, pass percentage
anam-khan

CBSE 12th Result 2026 Date LIVE: Class 12 marksheet on cbse.gov.in, DigiLocker soon; OSM system, passing marks

Latest Question