Question

The number of real roots of the polynomial equation x4 - x2 + 2x - 1 = 0 is

(a) 0

(b) 2

(c) 3

(d) 4

Answer 1

Answer is : (b) 2

Given,

⇒ x2 − x + 1 = 0 has no real roots.

⇒ x2 + x - 1 = 0 has two real roots