x²-2x+k-1=0Δ=4-4(k-1)≥0，解得k≤2x1+x2=2，x1*x2=k-1∴x1²+x2²=(x1+x2)²-2x1*x2=4-2(k-1)=6-2k=3解得k=3/2，满足要求望采纳
