抛物线y=x的平方-(k-1)x-3k-2与x轴于A(a,0),B(b,0)两点说明a,b是方程:x^2-(k-1)x-3k-2=0的根所以,a+b=k-1ab=-3k-2a^2+b^2=(a+b)^2-2ab=(k-1)^2+2(3k+2)=k^2+4k+5所以,k^2+4k+5=17k^2+4k-12=0(k+6)(k-2)=0k1=-6,k2=2...