Sail E0 Webinar
Question


Find the value of k for which x24x+k=0 has coincident roots.


Options:
A .   0
B .   -2
C .   4
D .   -4
Answer: Option C
:
C

On comparing x24x+k=0 with standard form ax2+bx+c=0, we get
a = 1, b = -4 and c = k
Now, discriminant, D = b24ac
D=(4)24(1)k=164k


The roots of quadratic equation are co-incident only when D=0.


 164k=0


 k=4



Was this answer helpful ?
Next Question

Submit Solution

Your email address will not be published.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

Latest Videos

Latest Test Papers