#(-x^4-3 x^3-2 x^2+7 x-7)/(x^2+3)#
#color(white)(......)color(white)(.....)-x^2-3x+1#
#x^2+3|overline(-x^4-3x^3-2x^2+7x-7)#
#color(white)(.............)ul(-x^4+"0"-3x^2)#
#color(white)(.....................)-3x^3+x^2+7x#
#color(white)(......................)ul(-3x^3+""0-9x)#
#color(white)(...................................)x^2+16x-7#
#color(white)(.....................................)ul(x^2+""0+3)#
#color(white)(.............................................)16x-10#
#(-x^4-3 x^3-2 x^2+7 x-7)/(x^2+3) = -x^2-3x+1+(16x-10)/(x^2+3)#