Let's do the division
color(white)(aaaa)aaaa6x^3-9x^2-12x-66x3−9x2−12x−6color(white)(aaaa)aaaa∣∣3x+43x+4
color(white)(aaaa)aaaa6x^3+8x^26x3+8x2color(white)(aaaaaaaaaaaaa)aaaaaaaaaaaaa∣∣2x^2-17/3x+32/92x2−173x+329
color(white)(aaaaa)aaaaa0-17x^2-12x0−17x2−12x
color(white)(aaaaaaa)aaaaaaa-17x^2-68/3x−17x2−683x
color(white)(aaaaaaaaaaa)aaaaaaaaaaa0+32/3x-60+323x−6
color(white)(aaaaaaaaaaaaa)aaaaaaaaaaaaa+32/3x+128/9+323x+1289
color(white)(aaaaaaaaaaaaaaa)aaaaaaaaaaaaaaa+0-182/9+0−1829
The quotient is =2x^2-17/3x+32/9=2x2−173x+329 and the remainder is =-182/9=−1829