x²y²+2xy-3 x²y²-xy-2 因式分解

x²y²+2xy-3 x²y²-xy-2 因式分解
x²y²+2xy-3 x²y²-xy-2 因式分解

x²y²+2xy-3 x²y²-xy-2 因式分解
x²y²+2xy-3
=(xy-1)(xy+3)
x²y²-xy-2
=(xy+1)(xy-2)

短轴长为2，则2b=2,b=1. 离心率为√3/2,则c/a=√3/2, 又因a^2=b^2+c^2,即a^2=1+c^2, 解得a=2,b=√3. 椭圆的方程x^2/4+y

=-x²y²+xy-2
=-（2x²y²-xy+2)
=-(xy-1)(2xy+1)-3

先设xy=A则x²y²=A²
A²+2A-3A²-A-2
=-2A²+A-2
=-2x²y²+xy-2