Find the Roots (Zeros) F(x)=x^4-6x^3+8x^2-21

$F (x) = x^{4} - 6 x^{3} + 8 x^{2} - 21$

Set $x^{4} - 6 x^{3} + 8 x^{2} - 21$ equal to $0$ .

$x^{4} - 6 x^{3} + 8 x^{2} - 21 = 0$

Graph each side of the equation. The solution is the x-value of the point of intersection.

$x \approx - 1.14052494, 4.43751454$