Question
Question: The set of values of l for which the equation 2x<sup>2</sup> –2(2l + 1)x + l(l + 1) = 0 has one roo...
The set of values of l for which the equation
2x2 –2(2l + 1)x + l(l + 1) = 0 has one root less than l and other root greater then l, will be-
A
–1 <l< 1
B
–1 <l< 0
C
lĪ(–, –1)Č(0, )
D
l Ī R
Answer
lĪ(–, –1)Č(0, )
Explanation
Solution
f(l) < 0 Ž 2l2 – 2(2l + 1)l + l(l + 1) < 0
Ž 2l2 – 4l2 – 2l + l2 + l < 0
Ž l2 + l > 0 Ž l Ī (–, –1) Č (0, )