Commerce Exam  >  Commerce Notes  >  Mathematics (Maths) Class 11  >  RD Sharma Class 11 Solutions Chapter - Ellipse

RD Sharma Class 11 Solutions Chapter - Ellipse | Mathematics (Maths) Class 11 - Commerce PDF Download

Download, print and study this document offline
Please wait while the PDF view is loading
 Page 1


26. Ellipse
Exercise 26.1
1. Question
Find the equation of the ellipse whose focus is (1, - 2), the directrix 3x – 2y + 5 = 0 and eccentricity equal to
1/2.
Answer
Given that we need to find the equation of the ellipse whose focus is S(1, - 2) and directrix(M) is 3x - 2y + 5
= 0 and eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 52x
2
 + 52y
2
 - 104x + 208y + 260 = 9x
2
 + 4y
2
 - 12xy - 20y + 30x + 25
? 43x
2
 + 48y
2
 + 12xy - 134x + 228y + 235 = 0
? The equation of the ellipse is 43x
2
 + 48y
2
 + 12xy - 134x + 228y + 235 = 0.
2 A. Question
Find the equation of the ellipse in the following cases:
focus is (0, 1), directrix is x + y = 0 and .
Answer
Page 2


26. Ellipse
Exercise 26.1
1. Question
Find the equation of the ellipse whose focus is (1, - 2), the directrix 3x – 2y + 5 = 0 and eccentricity equal to
1/2.
Answer
Given that we need to find the equation of the ellipse whose focus is S(1, - 2) and directrix(M) is 3x - 2y + 5
= 0 and eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 52x
2
 + 52y
2
 - 104x + 208y + 260 = 9x
2
 + 4y
2
 - 12xy - 20y + 30x + 25
? 43x
2
 + 48y
2
 + 12xy - 134x + 228y + 235 = 0
? The equation of the ellipse is 43x
2
 + 48y
2
 + 12xy - 134x + 228y + 235 = 0.
2 A. Question
Find the equation of the ellipse in the following cases:
focus is (0, 1), directrix is x + y = 0 and .
Answer
Given that we need to find the equation of the ellipse whose focus is S(0,1) and directrix(M) is x + y = 0 and
eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 8x
2
 + 8y
2
 - 16y + 8 = x
2
 + y
2
 + 2xy
? 7x
2
 + 7y
2
 - 2xy - 16y + 8 = 0
? The equation of the ellipse is 7x
2
 + 7y
2
 - 2xy - 16y + 8 = 0.
2 B. Question
Find the equation of the ellipse in the following cases:
focus is (- 1, 1), directrix is x - y + 3 = 0 and .
Answer
Given that we need to find the equation of the ellipse whose focus is S(- 1,1) and directrix(M) is x - y + 3 = 0
and eccentricity(e) is equal to .
Page 3


26. Ellipse
Exercise 26.1
1. Question
Find the equation of the ellipse whose focus is (1, - 2), the directrix 3x – 2y + 5 = 0 and eccentricity equal to
1/2.
Answer
Given that we need to find the equation of the ellipse whose focus is S(1, - 2) and directrix(M) is 3x - 2y + 5
= 0 and eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 52x
2
 + 52y
2
 - 104x + 208y + 260 = 9x
2
 + 4y
2
 - 12xy - 20y + 30x + 25
? 43x
2
 + 48y
2
 + 12xy - 134x + 228y + 235 = 0
? The equation of the ellipse is 43x
2
 + 48y
2
 + 12xy - 134x + 228y + 235 = 0.
2 A. Question
Find the equation of the ellipse in the following cases:
focus is (0, 1), directrix is x + y = 0 and .
Answer
Given that we need to find the equation of the ellipse whose focus is S(0,1) and directrix(M) is x + y = 0 and
eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 8x
2
 + 8y
2
 - 16y + 8 = x
2
 + y
2
 + 2xy
? 7x
2
 + 7y
2
 - 2xy - 16y + 8 = 0
? The equation of the ellipse is 7x
2
 + 7y
2
 - 2xy - 16y + 8 = 0.
2 B. Question
Find the equation of the ellipse in the following cases:
focus is (- 1, 1), directrix is x - y + 3 = 0 and .
Answer
Given that we need to find the equation of the ellipse whose focus is S(- 1,1) and directrix(M) is x - y + 3 = 0
and eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 8x
2
 + 8y
2
 + 16x - 16y + 16 = x
2
 + y
2
 - 2xy + 6x - 6y + 9
? 7x
2
 + 7y
2
 + 2xy + 10x - 10y + 7 = 0
? The equation of the ellipse is 7x
2
 + 7y
2
 + 2xy + 10x - 10y + 7 = 0.
2 C. Question
Find the equation of the ellipse in the following cases:
focus is (- 2, 3), directrix is 2x + 3y + 4 = 0 and 
Answer
Given that we need to find the equation of the ellipse whose focus is S(- 2,3) and directrix(M) is 2x + 3y + 4
= 0 and eccentricity(e) is equal to .
Page 4


26. Ellipse
Exercise 26.1
1. Question
Find the equation of the ellipse whose focus is (1, - 2), the directrix 3x – 2y + 5 = 0 and eccentricity equal to
1/2.
Answer
Given that we need to find the equation of the ellipse whose focus is S(1, - 2) and directrix(M) is 3x - 2y + 5
= 0 and eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 52x
2
 + 52y
2
 - 104x + 208y + 260 = 9x
2
 + 4y
2
 - 12xy - 20y + 30x + 25
? 43x
2
 + 48y
2
 + 12xy - 134x + 228y + 235 = 0
? The equation of the ellipse is 43x
2
 + 48y
2
 + 12xy - 134x + 228y + 235 = 0.
2 A. Question
Find the equation of the ellipse in the following cases:
focus is (0, 1), directrix is x + y = 0 and .
Answer
Given that we need to find the equation of the ellipse whose focus is S(0,1) and directrix(M) is x + y = 0 and
eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 8x
2
 + 8y
2
 - 16y + 8 = x
2
 + y
2
 + 2xy
? 7x
2
 + 7y
2
 - 2xy - 16y + 8 = 0
? The equation of the ellipse is 7x
2
 + 7y
2
 - 2xy - 16y + 8 = 0.
2 B. Question
Find the equation of the ellipse in the following cases:
focus is (- 1, 1), directrix is x - y + 3 = 0 and .
Answer
Given that we need to find the equation of the ellipse whose focus is S(- 1,1) and directrix(M) is x - y + 3 = 0
and eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 8x
2
 + 8y
2
 + 16x - 16y + 16 = x
2
 + y
2
 - 2xy + 6x - 6y + 9
? 7x
2
 + 7y
2
 + 2xy + 10x - 10y + 7 = 0
? The equation of the ellipse is 7x
2
 + 7y
2
 + 2xy + 10x - 10y + 7 = 0.
2 C. Question
Find the equation of the ellipse in the following cases:
focus is (- 2, 3), directrix is 2x + 3y + 4 = 0 and 
Answer
Given that we need to find the equation of the ellipse whose focus is S(- 2,3) and directrix(M) is 2x + 3y + 4
= 0 and eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 325x
2
 + 325y
2
 + 1300x - 1950y + 4225 = 64x
2
 + 144y
2
 + 192xy + 256x + 384y + 256
? 261x
2
 + 181y
2
 - 192xy + 1044x - 2334y + 3969 = 0
? The equation of the ellipse is 261x
2
 + 181y
2
 - 192xy + 1044x - 2334y + 3969 = 0.
2 D. Question
Find the equation of the ellipse in the following cases:
focus is (1, 2), directrix is 3x + 4y - 7 = 0 and .
Answer
Given that we need to find the equation of the ellipse whose focus is S(1, 2) and directrix(M) is 3x + 4y - 5 =
0 and eccentricity(e) is equal to .
Page 5


26. Ellipse
Exercise 26.1
1. Question
Find the equation of the ellipse whose focus is (1, - 2), the directrix 3x – 2y + 5 = 0 and eccentricity equal to
1/2.
Answer
Given that we need to find the equation of the ellipse whose focus is S(1, - 2) and directrix(M) is 3x - 2y + 5
= 0 and eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 52x
2
 + 52y
2
 - 104x + 208y + 260 = 9x
2
 + 4y
2
 - 12xy - 20y + 30x + 25
? 43x
2
 + 48y
2
 + 12xy - 134x + 228y + 235 = 0
? The equation of the ellipse is 43x
2
 + 48y
2
 + 12xy - 134x + 228y + 235 = 0.
2 A. Question
Find the equation of the ellipse in the following cases:
focus is (0, 1), directrix is x + y = 0 and .
Answer
Given that we need to find the equation of the ellipse whose focus is S(0,1) and directrix(M) is x + y = 0 and
eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 8x
2
 + 8y
2
 - 16y + 8 = x
2
 + y
2
 + 2xy
? 7x
2
 + 7y
2
 - 2xy - 16y + 8 = 0
? The equation of the ellipse is 7x
2
 + 7y
2
 - 2xy - 16y + 8 = 0.
2 B. Question
Find the equation of the ellipse in the following cases:
focus is (- 1, 1), directrix is x - y + 3 = 0 and .
Answer
Given that we need to find the equation of the ellipse whose focus is S(- 1,1) and directrix(M) is x - y + 3 = 0
and eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 8x
2
 + 8y
2
 + 16x - 16y + 16 = x
2
 + y
2
 - 2xy + 6x - 6y + 9
? 7x
2
 + 7y
2
 + 2xy + 10x - 10y + 7 = 0
? The equation of the ellipse is 7x
2
 + 7y
2
 + 2xy + 10x - 10y + 7 = 0.
2 C. Question
Find the equation of the ellipse in the following cases:
focus is (- 2, 3), directrix is 2x + 3y + 4 = 0 and 
Answer
Given that we need to find the equation of the ellipse whose focus is S(- 2,3) and directrix(M) is 2x + 3y + 4
= 0 and eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 325x
2
 + 325y
2
 + 1300x - 1950y + 4225 = 64x
2
 + 144y
2
 + 192xy + 256x + 384y + 256
? 261x
2
 + 181y
2
 - 192xy + 1044x - 2334y + 3969 = 0
? The equation of the ellipse is 261x
2
 + 181y
2
 - 192xy + 1044x - 2334y + 3969 = 0.
2 D. Question
Find the equation of the ellipse in the following cases:
focus is (1, 2), directrix is 3x + 4y - 7 = 0 and .
Answer
Given that we need to find the equation of the ellipse whose focus is S(1, 2) and directrix(M) is 3x + 4y - 5 =
0 and eccentricity(e) is equal to .
Let P(x,y) be any point on the ellipse.
We know that the distance between the focus and any point on the ellipse is equal to the eccentricity times
the perpendicular distance from that point to the directrix.
We know that distance between the points (x
1
,y
1
) and (x
2
,y
2
) is .
We know that the perpendicular distance from the point (x
1
,y
1
) to the line ax + by + c = 0 is .
? SP = ePM
? SP
2
 = e
2
PM
2
? 
? 
? 
? 100x
2
 + 100y
2
 - 200x - 400y + 500 = 9x
2
 + 16y
2
 + 24xy - 30x - 40y + 25
? 91x
2
 + 84y
2
 - 24xy - 170x - 360y + 475 = 0
? The equation of the ellipse is 91x
2
 + 84y
2
 - 24xy - 170x - 360y + 475 = 0.
3 A. Question
Find the eccentricity, coordinates of foci, length of the latus - rectum of the following ellipse:
4x
2
 + 9y
2
 = 1
Answer
Given the equation of the ellipse is 4x
2
 + 9y
2
 = 1.
We need to find the eccentricity, coordinates of foci and length of latus rectum.
Read More
75 videos|238 docs|91 tests

Top Courses for Commerce

75 videos|238 docs|91 tests
Download as PDF
Explore Courses for Commerce exam

Top Courses for Commerce

Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev
Related Searches

practice quizzes

,

MCQs

,

RD Sharma Class 11 Solutions Chapter - Ellipse | Mathematics (Maths) Class 11 - Commerce

,

RD Sharma Class 11 Solutions Chapter - Ellipse | Mathematics (Maths) Class 11 - Commerce

,

mock tests for examination

,

Viva Questions

,

Free

,

Important questions

,

video lectures

,

study material

,

pdf

,

RD Sharma Class 11 Solutions Chapter - Ellipse | Mathematics (Maths) Class 11 - Commerce

,

Summary

,

past year papers

,

shortcuts and tricks

,

Previous Year Questions with Solutions

,

Objective type Questions

,

Exam

,

Sample Paper

,

ppt

,

Extra Questions

,

Semester Notes

;