Consider the polynomial P(x)=x4−2x3+4x2−2x+3P(x) = x^4 - 2x^3 + 4x^2 - 2x + 3P(x)=x4−2x3+4x2−2x+3. Which of the following is true about its roots?
All roots are real
All roots are purely imaginary
It has no real roots
It has exactly one real root