[单选题]P是双曲线(a>0,b>0)上的点,F1,F2是其焦点,双曲线的离心率是,且=0,若△F1PF2的面积是9,则a+b的值等于( )A.4B.7C.6D.5
[单选题]He is sure to ________ with the help of Mrs. Li.A.make a progressB.make progressesC.make the progressD.make progress
[单选题]Lucy was called to ____ her stupid deeds the night before, but she couldn’t remember anything. A. pay for B. leave for B. account for D. look for
[单选题]A.though a snowstorm is in store,people are still looking forward________the plan to go sightseeing in Lhasa.[ ]A.to cancelingB.not to cancelingC.not to cancelD.to not canceling
[单选题]平面向量与的夹角为2丌Ia=(3.0),b|=2,则la+2b=( )A.13B.37C.7D.3
[单选题]Teaching pronunciation class to a mixed group of learners can ________ a teacher with many challenging problems.A.provideB.produceC.present D.offer
[单选题]已知非零向量满足,则△A.C为( )A.三边均不相等的三角形B.直角三角形C.等腰非等边三角形 D.等边三角形
[单选题]设数列是等比数列,则“a1<a3<”是“数列为递增数列”的( )A.充分而不必要条件B.必要而不充分条件C.充分必要条件D.既不充分也不必要条件
[单选题]His efforts to raise money for his program were ________ because no one showed any intention to take a cent out of their pockets.[ ]A.in placeB.in sightC.in effectD.in vain
[单选题]已知四边形A.CD的三个顶点A(0,2),B(-1,-2),C(3,1),且,则顶点D的坐标为[ ]A.B.C.(3,2) D.(1,3)
[单选题]The shop assistant was dismissed as she was_______of cheating customers’.A.accusedB.chargedC.scolded D.cursed
[单选题]△ABC中,点D、E、F分别为AB、BC、CA的中点,则AFDB=( ) A. FDB. FCC. FED. BE
[单选题]_____ students are practicing ______ English with each other at the English corner.A. The number of; speaking B. A great deal of; to speakC. A number of; to speak D. A great many; speaking
[单选题]Nothing is so easy as ________ parents to raise their expectations of their children too high.A.ofB.forC.byD.to
[单选题]It is reported that the scientists in our country are_______all possible way to control H7N9 flu.?A.operatingB.solvingC.explodingD.exploring
[单选题]In order to finish the task______, she works day and night and doesnt measure the cost to her health.[ ]A.on purposeB.in advanceC.in additionD.as usual
[单选题]已知向量=(4,x),=(-4,4),若、平行,则x的值为[ ]A.0 B.-4 C.4 D.x=±4
[单选题](2011?重庆)“x<﹣1”是“x2﹣1>0”的( )A.充分而不必要条件B.必要而不充分条件C.充要条件D.既不充分也不必要条件
[单选题]已知命题p所有指数函数都是单调函数,则为( )A.所有指数函数都不是单调函数B.所有单调函数都不是指数函数C.存在一个指数函数,它不是单调函数D.存在一个单调函数,它不是指数函数
[计算题]已知p:方程x2+mx+1=0有两个不等的负实根,q:方程4x2+4(m-2)+1=0无实根.若p或q 为真,p且q为假,求实数m的取值范围.
[单选题]–I was surprised to see wild flowers in Alaska.--Many people think there is nothing ice and snow.A.except forB.rather thanC.apart fromD.regardless of