Let's perform the synthetic division
color(white)(aaaa)-2|color(white)(aaaa)-1color(white)(aaaa)-1color(white)(aaaaaa)1color(white)(aaaa)-1color(white)(aaaaaa)2
color(white)(aaaaaaa)#|color(white)(aaaa)##color(white)(aaaaaaaa)2#color(white)(aaaaa)-2color(white)(aaaaa)2color(white)(aaaa)-2
color(white)(aaaaaaaaa)_________________________________________________________##
color(white)(aaaaaaa)#|color(white)(aaaa)#-1color(white)(aaaaaa)1color(white)(aaaa)-1color(white)(aaaaa)1color(white)(aaaaaa)color(red)(0)
The remainder is 0 and the quotient is =-x^3+x^2-x+1