Solve the quartic equation [math]x^4+3x-2=0[/math].

As you can see from the graph, 0.62 and -1.62 are the only real roots. I used the complex root tool on GeoGebra to find the complex roots. The complex roots are 0.5+1.32[i]i[/i] and 0.5-1.32[i]i.[/i]