Let's do the long division color(white)(aa)4x^3-6x^2color(white)(aaaaa) +6color(white)(aa)∣2x+3 color(white)(aa)4x^3+6x^2color(white)(aaaaaaaaaa)∣2x^2-6x+9 color(white)(aaa)0-12x^2 color(white)(aaaaa)-12x^2-18x color(white)(aaaaaaaaa)0+18x+6 color(white)(aaaaaaaaaaa)+18x+27 color(white)(aaaaaaaaaaaaaaa)0-21