∵x^2/16+y^2/9=1、
∴椭圆焦点为(√7,0),(-√7,0),c^2=7
长轴端点为(4,0)(-4,0) 短轴端点为(0,3)(0,-3)
∵双曲线以椭圆x^2/16+y^2/9=1的顶点为焦点,且过椭圆焦点
∴设[x^2/(16-b^2)]-(y^2/b^2)=1或[y^2/(16-b^2)]-x^2/b^2=1
①[x^2/(16-b^2)]-(y^2/b^2)=1
[7/(16-b^2)]=1
∴b^2=9,a^2=7
②[y^2/(16-b^2)]-x^2/b^2=1
[9^2/(16-b^2)]=1
∴b^2=7,a^2=9
即双曲线方程为(x^2/7)-(y^2/9)=1或(y^2/9)-(x^2/7)=1