1.x^2/16+y^2/4=1,a=4,b=2,c=√(a2-b2)=2√3,e=c/a=√3/2长轴2a=8,短轴2b=4,离心率e=√3/2,顶点(4,0)(-4,0)(0,2)(0,-2),焦点(2√3,0)(-2√3,0)2.x^2/9+y^2/81=1,a=9,b=3,c=√(a2-b2)=6√2,e=c/a=2√2/3长轴2a=18,短...