已知双曲线的一条渐近线为x+3y=0,且与椭圆x2+4y2=64有相同的焦距,求

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问题:

已知双曲线的一条渐近线为x+
3
y=0
,且与椭圆x2+4y2=64有相同的焦距,求双曲线的标准方程.
考点:椭圆的性质(顶点、范围、对称性、离心率)双曲线的性质(顶点、范围、对称性、离心率)
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一个高是1.2米,体积是3.6立方米的圆锥体,它的底面面积是______平方米.

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Motivation is "the driving force within individuals that impels them to action." And goals are the sought-after results_____(1) motivated behavior.Motivation can be either positive or negative_____(2) direction. We may feel a driving force toward some object or condition, _____(3) a driving force away from some object or condition. For example, a person may be impelled toward a restaurant to fulfill a need, hunger, and away_____(4) an airplane to fulfill a need of safety. Some psychologists refer to positive drives_____(5) needs, wants or desires,_____(6) negative drives as fears or aversions._____ (7), though negative and positive motivational forces seem to differ dramatically_____(8) terms of physical and sometimes emotional activity, they are basically similar in_____(9) they both serve to initiate and sustain human behavior.____(10) this reason, researchers often refer _____(11) both kinds of drives or motives as needs, wants and desires.Goals, _____(12), can be either positive or negative. A positive goal is one toward_____ (13) behavior is directed and it is often referred to as an approach object. A negative goal is _____(14) from which behavior is directed away and it is sometimes referred to as an avoidance object. Since both approach and avoidance goals can be considered objectives of motivated behavior, most researchers refer to_____(15) types simply as goals. Consider this example. A middle-aged woman may wish to remain_____(16) attractive as possible. Her positive goal is to appear desirable, and_____(17) she may use a perfume advertised to make her irresistible. A negative goal may be to prevent her skin_____(18) aging, and therefore she may buy and use face creams._____(19) the former case, she uses perfume to help her achieve her positive goal — attractiveness; in the____(20) case, she uses face creams to help avoid a negative goal — wrinkled skin.

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如果银行的存款准备金率为100%,公众把存款中的20%作为通货持有,那么货币乘数是()

A、3.33

B、3

C、4

D、10

题型:解答题

工业上生产“的确良”通常用乙二醇、对苯二甲酸为原料,反应式为:

nHOCH2CH2OH+ +(2n-1)H2O,合成时,若消耗乙二醇的物质的量比对苯二甲酸多5‰,上述聚合物的链节数n为[ ]

A.100

B.200

C.300

D.400

题型:解答题

某建设工程中,发包人的支付担保应是( )。

A.设备担保
B.土地担保
C.原料担保
D.金额担保

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