已知双曲线x2a2-y2b2=1(a>0,b>0)的离心率为3,则双曲线的渐近线

题型:选择题

问题:

已知双曲线
x2
a2
-
y2
b2
=1(a>0,b>0)
的离心率为
3
,则双曲线的渐近线方程为(  )
A.y=±
2
2
x
B.y=±
2
x
C.y=±2xD.y=±
1
2
x
考点:双曲线的性质(顶点、范围、对称性、离心率)
题型:选择题

第三部分:写作(共三节,满分55分)

第一节:单词拼写(共10小题,每题1分,满分10分)

66.She cried,         (撕扯)her newly bought skirt into pieces.

67.Children need lots of       (鼓励)when they are learning new things.

68.I don’t think the color on this TV is properly        (调整).

69.Smoking is strictly       (禁止)in or near the gas station.

70.It’s very difficult to breathe at high      (海拔).

71.He    (全神贯注)on what the teacher said, not noticing what happened outside the window.

72.Your work will be      (评价)by members of the management team.

73.The exercises are designed to     (增强)your arm muscles.

74.The game had to be     (放弃)due to bad weather.

75.She spent the afternoon     (漂浮)on her back in the pool.

题型:选择题

“星星之火,可以燎原”,在革命年代,毛 * * 曾写下这样的诗句来形容当年革命的大好形势。这里的“星星之火”指的是哪一革命根据地[ ]

A.井冈山根据地

B.陕甘根据地

C.左右江根据地

D.中央根据地

题型:选择题

以下属于人文景观的是( )。

A.甘肃敦煌莫高窟

B.江西庐山

C.四川九寨沟

D.吉林长白山天池

题型:选择题

下列对焊媒的描述,错误的是

A.焊媒的作用是清除焊件、焊料表面的氧化膜
B.焊媒能改善熔化后焊料的润湿性
C.焊媒能降低被焊金属的熔点
D.焊媒的熔点及作用温度低于焊料
E.焊媒及其生成物比重应小,残渣易去除

题型:选择题

韶山4型电力机车构架与轴箱吊环处垂直距离原型为()。

A.40mm

B.43mm

C.45mm

D.47mm

更多题库