Question

5. If the equation x2 - kx + 1, have no real roots, then
(a)-2 <k<2
(b) -3<k<3
(c) k >2
(d) k< -2​

Answer 1

Answer:

-2 <k <2

Step-by-step explanation:

quadratic : x^2-kx +1

conditions for no real root :

discriminant ( delta)<0

a= 1 , b= -k c= 1

D = b^2- 4ac

D = (-k)^2- 4x1x1

D= k^2 - 4

k^2 - 4 <0

( k+2)(k-2)<0

k (-2 ,+2)

-2 <k <2