因为x=-1-√2,所以x+1=-√2,(x+1)^2=2,展开,整理得x^2+2x-1=0
于是x^5+4x^4+6x^3+6x²+2x+3=(x^2+2x-1)(x^3+2x^2+3x+2)+x+5=x+5=4-√2