Help with Max number of Roots? Algebra

Question

Find the maximum number of roots of P(x) = x³ + 3x.


a) 1

b) 2

c) 3

d) 4

Answer 1

P(x)=x^3+3x

x^3+3x=0

x(x^2+3)=0

x=0

x^2+3=0

x^2=-3

x=±√-3

x=±(√3)i

x=0, x=(√3)i, x=(-√3)i

there are 3 roots, C)