(k+1)x^2-(k^2+3k)x+k^2-1=0
①当K+1≠0,即K≠-1时,
[(K+1)X+(K-1)][X+(K+1)]=0
X1=(1-K)/(K+1),X2=-K-1;
②当K+1=0,即K=-1时,原方程化为:2X=0,
X=0
kx^2+2(k-2)x+k-3=0
①当K=0时,原方程化为:-4X-3=0,
X=-3/4;
②当K≠0时,
Δ=4(K-2)^2-4K(K-3)
=-4K+16,
1)当-4K+16≥0,即K≤4(K≠0)时,
X=[-2(K-2)±√(16-4K)]/(2K),
2)当-4K+164时,没有实数根.