由x=√3-1 得x²=4-2√3 则x²+2x=4-2√3+2√3-2=2(3-2x²-4x)/(x²+2x-1)= [3-2(x²+2x)]/(x²+2x-1)= (3-4)/(2-1)=-1
3-2x^2-4x=-2[x+½(2-√10)][x+½(2+√10)]
解:﹣2x²-4x+3 =﹣2﹙x²+2x+1-5/2﹚ =﹣2[﹙x+1﹚²-﹙√10/2﹚²] =﹣2﹙x+1-√10/2﹚﹙x+1+√10/2﹚
十字相乘法即可求出