Sail E0 Webinar
Question
If x is real and k=x2x+1x2+x+1, then  
Options:
A .  13≤k≤3
B .  k ≥ 5
C .  k ≤ 0
D .  k ≤ 4
Answer: Option A
:
A
Fromk=x2x+1x2+x+1
We have x2(k1)+x(k+1)+k1=0
As given, x is real ⇒ (k+1)24(k1)20
3k210k+30
Which is possible only when the value of k lies between the roots of the equation3k210k+3=0
That is, when 13k3 {Since roots are 13 and 3}

Was this answer helpful ?
Next Question

Submit Solution

Your email address will not be published. Required fields are marked *

Latest Videos

Latest Test Papers