1.判斷 (1)雙曲線x^2/a^2 -y^2/b^2 =1與y^2/a^2 -x^2/b^2 =1(a>0,b>0)的形狀相同. ( )(2)雙曲線x^2/a^2 -y^2/b^2 =1與y^2/a^2 -x^2/b^2 =1(a>0,b>0)的漸近線相同. ( )(3)等軸雙曲線的漸近線互相垂直. ( )答案:(1)√ (2)× (3)√ 2.圓錐曲線x^2/(m+8)+y^2/9=1的離心率e=2,則實(shí)數(shù)m的值為( )A.-5 B.-35 C.19 D.-11解析:由圓錐曲線x^2/(m+8)+y^2/9=1的離心率e=2,說明曲線是雙曲線,所以m0,n>0)的半實(shí)軸長(zhǎng)、半虛軸長(zhǎng)、焦點(diǎn)坐標(biāo)、離心率、頂點(diǎn)坐標(biāo)和漸近線方程.解:把方程nx2-my2=mn(m>0,n>0)化為標(biāo)準(zhǔn)方程為x^2/m-y^2/n=1(m>0,n>0),