Given equation is x2 + 4ix – 4 = 0
Comparing with ax2 + bx + c = 0, we get
a = 1, b = 4i, c = -4
Discriminant = b2 – 4ac
= (4i)2 – 4 × 1 × (-4)
= 16i2 + 16
= -16 + 16 …..[∵ i = -1]
= 0
So, the given equation has equal roots.
These roots are given by
∴ x = -2i
∴ The root of the given equation is -2i.