Defence Exam  >  Defence Questions  >  If the roots of the equation x2 + px+ q= 0 ar... Start Learning for Free
If the roots of the equation x2 + px + q = 0 are in the same ratio as those of the equation x2 + lx + m = 0, then which one of the following is correct?
  • a)
    p2m = l2q
  • b)
    m2p = l2q
  • c)
    m2p = q2l
  • d)
    m2p2 = l2q
Correct answer is option 'A'. Can you explain this answer?
Verified Answer
If the roots of the equation x2 + px+ q= 0 are in the same ratio as th...
Let α, kα be roots of x2 + px + q = 0 and β , kβ be roots of x2 + ℓx + m = 0 Clearly,
View all questions of this test
Most Upvoted Answer
If the roots of the equation x2 + px+ q= 0 are in the same ratio as th...
Given equations:
1) x^2 + px + q = 0
2) x^2 + lx + m = 0

Let the roots of equation 1 be α and β, and the roots of equation 2 be ξ and η.

Ratio of roots:
The roots of a quadratic equation ax^2 + bx + c = 0 are given by the formula:

x = (-b ± √(b^2 - 4ac))/(2a)

From the above equation, we can see that if x1 and x2 are the roots of a quadratic equation, then the ratio of the roots is given by:

x1/x2 = (-b + √(b^2 - 4ac))/(-b - √(b^2 - 4ac))
= (√(b^2 - 4ac) - b)/(-√(b^2 - 4ac) - b)
= - (√(b^2 - 4ac) - b)/(√(b^2 - 4ac) + b)

Let's find the roots of equations 1 and 2 and compare their ratios.

Roots of equation 1:
Using the quadratic formula, we have:

α = (-p + √(p^2 - 4q))/2
β = (-p - √(p^2 - 4q))/2

Ratio of roots of equation 1:
α/β = (-p + √(p^2 - 4q))/(-p - √(p^2 - 4q))
= (√(p^2 - 4q) - p)/(-√(p^2 - 4q) - p)
= - (√(p^2 - 4q) - p)/(√(p^2 - 4q) + p)

Roots of equation 2:
Using the quadratic formula, we have:

ξ = (-l + √(l^2 - 4m))/2
η = (-l - √(l^2 - 4m))/2

Ratio of roots of equation 2:
ξ/η = (-l + √(l^2 - 4m))/(-l - √(l^2 - 4m))
= (√(l^2 - 4m) - l)/(-√(l^2 - 4m) - l)
= - (√(l^2 - 4m) - l)/(√(l^2 - 4m) + l)

Given that the ratios of the roots are the same, we can equate α/β and ξ/η:

- (√(p^2 - 4q) - p)/(√(p^2 - 4q) + p) = - (√(l^2 - 4m) - l)/(√(l^2 - 4m) + l)

Simplifying the equation:
(√(p^2 - 4q) - p)/(√(p^2 - 4q) + p) = (√(l^2 - 4m) - l)/(√(l^2 - 4m) + l)

Explore Courses for Defence exam
If the roots of the equation x2 + px+ q= 0 are in the same ratio as those of the equation x2 + lx+ m= 0, then which one of the following is correct?a)p2m= l2qb)m2p= l2qc)m2p= q2ld)m2p2 = l2qCorrect answer is option 'A'. Can you explain this answer?
Question Description
If the roots of the equation x2 + px+ q= 0 are in the same ratio as those of the equation x2 + lx+ m= 0, then which one of the following is correct?a)p2m= l2qb)m2p= l2qc)m2p= q2ld)m2p2 = l2qCorrect 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 If the roots of the equation x2 + px+ q= 0 are in the same ratio as those of the equation x2 + lx+ m= 0, then which one of the following is correct?a)p2m= l2qb)m2p= l2qc)m2p= q2ld)m2p2 = l2qCorrect 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 If the roots of the equation x2 + px+ q= 0 are in the same ratio as those of the equation x2 + lx+ m= 0, then which one of the following is correct?a)p2m= l2qb)m2p= l2qc)m2p= q2ld)m2p2 = l2qCorrect answer is option 'A'. Can you explain this answer?.
Solutions for If the roots of the equation x2 + px+ q= 0 are in the same ratio as those of the equation x2 + lx+ m= 0, then which one of the following is correct?a)p2m= l2qb)m2p= l2qc)m2p= q2ld)m2p2 = l2qCorrect 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 If the roots of the equation x2 + px+ q= 0 are in the same ratio as those of the equation x2 + lx+ m= 0, then which one of the following is correct?a)p2m= l2qb)m2p= l2qc)m2p= q2ld)m2p2 = l2qCorrect answer is option 'A'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of If the roots of the equation x2 + px+ q= 0 are in the same ratio as those of the equation x2 + lx+ m= 0, then which one of the following is correct?a)p2m= l2qb)m2p= l2qc)m2p= q2ld)m2p2 = l2qCorrect answer is option 'A'. Can you explain this answer?, a detailed solution for If the roots of the equation x2 + px+ q= 0 are in the same ratio as those of the equation x2 + lx+ m= 0, then which one of the following is correct?a)p2m= l2qb)m2p= l2qc)m2p= q2ld)m2p2 = l2qCorrect answer is option 'A'. Can you explain this answer? has been provided alongside types of If the roots of the equation x2 + px+ q= 0 are in the same ratio as those of the equation x2 + lx+ m= 0, then which one of the following is correct?a)p2m= l2qb)m2p= l2qc)m2p= q2ld)m2p2 = l2qCorrect answer is option 'A'. Can you explain this answer? theory, EduRev gives you an ample number of questions to practice If the roots of the equation x2 + px+ q= 0 are in the same ratio as those of the equation x2 + lx+ m= 0, then which one of the following is correct?a)p2m= l2qb)m2p= l2qc)m2p= q2ld)m2p2 = l2qCorrect 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