Question
Question: If p, q \> 0 and p \< q and a № 0 if px<sup>2</sup> + 4µxy + qy<sup>2</sup> + 4a(x + y + 1) = 0 re...
If p, q > 0 and p < q and a № 0 if
px2 + 4µxy + qy2 + 4a(x + y + 1) = 0
represents a pair of straight lines, then –
A
pЈ a Ј q
B
a Ј p
C
a і p
D
a Ј p or a і q
Answer
a Ј p or a і q
Explanation
Solution
Using D = 0 16aµ2–16a2µ+4a[(p+q)a–pq]=0
Since µ О R D і 0 gives (a – p) (a – q) і 0