Defence Exam  >  Defence Questions  >  Consider any point P on the ellipse x2/25 + y... Start Learning for Free
Consider any point P on the ellipse x2/25 + y2/9= 1 in the first quadrant. Let r and s represent its distances from (4,0) and ( - 4 , 0 ) respectively, th en (r + s) is equal to
  • a)
    10 unit
  • b)
    9 unit
  • c)
    8 unit
  • d)
    6 unit
Correct answer is option 'A'. Can you explain this answer?
Verified Answer
Consider any point P on the ellipse x2/25 + y2/9= 1 in the first quadr...
View all questions of this test
Most Upvoted Answer
Consider any point P on the ellipse x2/25 + y2/9= 1 in the first quadr...
Explanation:

Given equation of the ellipse is x^2/25 + y^2/9 = 1.

Let P(x, y) be any point on the ellipse in the first quadrant.

We are given two points (4, 0) and (-4, 0) and we need to find the distances r and s of point P from these points.

Step 1: Find the coordinates of point P

Let's assume that the x-coordinate of P is a, where a > 0. Then, we can find the y-coordinate of P using the equation of the ellipse:

a^2/25 + y^2/9 = 1

Simplifying the equation, we get:

y^2 = 9 - (9/25)a^2

Taking the square root on both sides, we obtain:

y = ±sqrt(9 - (9/25)a^2)

Since P is in the first quadrant, y > 0. Therefore, we can write:

y = sqrt(9 - (9/25)a^2)

So, the coordinates of point P are (a, sqrt(9 - (9/25)a^2)).

Step 2: Find the distances r and s

The distance between two points (x1, y1) and (x2, y2) is given by the formula:

d = sqrt((x2 - x1)^2 + (y2 - y1)^2)

For point P and (4, 0), the distance r is given by:

r = sqrt((4 - a)^2 + (0 - sqrt(9 - (9/25)a^2))^2)

Simplifying the equation, we get:

r = sqrt((16 - 8a + a^2) + (9 - (9/25)a^2))

r = sqrt(25 - (8a - a^2) + 9 - (9/25)a^2)

r = sqrt(34 - (8a - a^2) - (9/25)a^2)

Similarly, for point P and (-4, 0), the distance s is given by:

s = sqrt((-4 - a)^2 + (0 - sqrt(9 - (9/25)a^2))^2)

Simplifying the equation, we get:

s = sqrt((16 + 8a + a^2) + (9 - (9/25)a^2))

s = sqrt(25 + (8a + a^2) + 9 - (9/25)a^2)

s = sqrt(34 + (8a + a^2) - (9/25)a^2)

Step 3: Find the sum of distances r and s

(r + s) = sqrt(34 - (8a - a^2) - (9/25)a^2) + sqrt(34 + (8a + a^2) - (9/25)a^2)

Simplifying the equation, we get:

(r + s) = sqrt(68 + 2(8a + a^2) - 2(9/25)a^2)

(r + s) = sqrt(68 + 16a + 2a^2 - (18/25)a^
Explore Courses for Defence exam
Consider any point P on the ellipse x2/25 + y2/9= 1 in the first quadrant. Let r and s represent its distances from (4,0) and ( - 4 , 0 ) respectively, th en (r + s) is equal toa)10 unitb)9 unitc)8 unitd)6 unitCorrect answer is option 'A'. Can you explain this answer?
Question Description
Consider any point P on the ellipse x2/25 + y2/9= 1 in the first quadrant. Let r and s represent its distances from (4,0) and ( - 4 , 0 ) respectively, th en (r + s) is equal toa)10 unitb)9 unitc)8 unitd)6 unitCorrect answer is option 'A'. Can you explain this answer? for Defence 2024 is part of Defence preparation. The Question and answers have been prepared according to the Defence exam syllabus. Information about Consider any point P on the ellipse x2/25 + y2/9= 1 in the first quadrant. Let r and s represent its distances from (4,0) and ( - 4 , 0 ) respectively, th en (r + s) is equal toa)10 unitb)9 unitc)8 unitd)6 unitCorrect answer is option 'A'. Can you explain this answer? covers all topics & solutions for Defence 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Consider any point P on the ellipse x2/25 + y2/9= 1 in the first quadrant. Let r and s represent its distances from (4,0) and ( - 4 , 0 ) respectively, th en (r + s) is equal toa)10 unitb)9 unitc)8 unitd)6 unitCorrect answer is option 'A'. Can you explain this answer?.
Solutions for Consider any point P on the ellipse x2/25 + y2/9= 1 in the first quadrant. Let r and s represent its distances from (4,0) and ( - 4 , 0 ) respectively, th en (r + s) is equal toa)10 unitb)9 unitc)8 unitd)6 unitCorrect answer is option 'A'. Can you explain this answer? in English & in Hindi are available as part of our courses for Defence. Download more important topics, notes, lectures and mock test series for Defence Exam by signing up for free.
Here you can find the meaning of Consider any point P on the ellipse x2/25 + y2/9= 1 in the first quadrant. Let r and s represent its distances from (4,0) and ( - 4 , 0 ) respectively, th en (r + s) is equal toa)10 unitb)9 unitc)8 unitd)6 unitCorrect answer is option 'A'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of Consider any point P on the ellipse x2/25 + y2/9= 1 in the first quadrant. Let r and s represent its distances from (4,0) and ( - 4 , 0 ) respectively, th en (r + s) is equal toa)10 unitb)9 unitc)8 unitd)6 unitCorrect answer is option 'A'. Can you explain this answer?, a detailed solution for Consider any point P on the ellipse x2/25 + y2/9= 1 in the first quadrant. Let r and s represent its distances from (4,0) and ( - 4 , 0 ) respectively, th en (r + s) is equal toa)10 unitb)9 unitc)8 unitd)6 unitCorrect answer is option 'A'. Can you explain this answer? has been provided alongside types of Consider any point P on the ellipse x2/25 + y2/9= 1 in the first quadrant. Let r and s represent its distances from (4,0) and ( - 4 , 0 ) respectively, th en (r + s) is equal toa)10 unitb)9 unitc)8 unitd)6 unitCorrect answer is option 'A'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice Consider any point P on the ellipse x2/25 + y2/9= 1 in the first quadrant. Let r and s represent its distances from (4,0) and ( - 4 , 0 ) respectively, th en (r + s) is equal toa)10 unitb)9 unitc)8 unitd)6 unitCorrect answer is option 'A'. Can you explain this answer? tests, examples and also practice Defence tests.
Explore Courses for Defence exam
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