(x² + 1)² − x² = 0 has
(3)
Given equation: (x² + 1)² − x² = 0 ⇒ (x² + 1 − x)(x² + 1 + x) = 0.
⇒ (x² − x + 1)(x² + x + 1) = 0 or x² − x + 1 = 0, Its discriminant D = (−1)² − 4×1×1 = −3 < 0 Its discriminant D = 1² − 4×1×1 = −3 < 0
So, there are no real roots.