Question
Question: If the roots of equation \(\frac{1}{x + p} + \frac{1}{x + q} = \frac{1}{r}\) are equal in magnitude ...
If the roots of equation x+p1+x+q1=r1 are equal in magnitude but opposite in sign, then (p+q)=
A
2r
B
r
C
– 2r
D
None of these
Answer
2r
Explanation
Solution
Given equation can be written as
x2+(p+q−2r)x+[pq−(p+q)r]=0
Since the roots are equal and of opposite sign,
∴ Sum of roots = 0
⇒ −(p+q−2r)=0 ⇒ p+q=2r