[单选题]已知a=(cosx,sinx),b=(sinx,cosx),记f(x)=a·b,要得到函数y=sin⁴x-cos⁴x的图像,只需将函数y=f(x)的图像
A.向左平移个单位长度
B.向右平移个单位长度
C.向左平移个单位长度
D.向右平移个单位长度

• [单选题]You neednt have apologized for your absence_______, it s hardly your fault.A.besidesB.thereforeC.howeverD.meanwhile

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• [单选题]已知命题p:彐x∈R,使tanx=1,其中正确的是[ ]A.p:彐x∈R,使tanx≠1　　B.p:彐xR,使tanx≠1　　C.p:yx∈R,使tanx≠1　　D.p:yxR,使tanx≠1

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• [单选题]The suspect ?for some way of escaping from the police car , but in vain .A.showed offB.cast aboutC.put downD.turned away

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• [单选题]The astronauts have to lie ________ the floor of the spaceship to fight against the great pressure during the flight. A.inB.beyondC.againstD.at

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• [单选题]Your friend is _______. Does he often _______ you?A.a great fun; make funs of B.good fun; make fun ofC.very funny; play a joke of D.fun; be laughed by

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• [单选题]以q为公比的等比数列{an}中,a1＞0,则“a ＜a”是“9＞”的( )A.必要而不充分条件B.充分而不必要条件C.充分必要条件D.既不充分也不必要条件

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• [单选题]Was it an accident or did David do it ________?A.on purposeB.at onceC.in timeD.as usual

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• [单选题]Many people who had seen the film were afraid to go tothe forest when they remembered the scenes____ people were eaten by the tiger.[ ]A. in whichB. by which C. which D. that

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• [单选题]Children need a lot to grow up, but ________ they need love and care.A.above allB.in allC.at allD.after all

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• [单选题]命题p:若a、b∈R,则|a|+|b|＞1是|a+b|＞1的充要条件；命题q:函数y=的定义域是(-∞,-1]∪[3,+∞),则[ ]A.“p或q”为假B.“p且q”为真C.p真q假 D.p假q真

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• [单选题]Youd better take something to read when you go to see the doctor________you have to wait. [ ]A. even ifB. as ifC. in caseD. in order that

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• [单选题]Be sure to read the ________ before you take the medicine.A.commandsB.situationsC.expressionsD.directions

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• [单选题]The speech by the headmaster given on my graduation ceremony is strongly impressed ___ my memory.A.toB.overC.byD.on

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• [单选题]Not many people __________ the idea that money brings happiness.A.in favor ofB.agreeC.subscribe toD.approve

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• [计算题]设命题,命题, 若 是 的必要不充分条件,求实数的取值范围.

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• [单选题]A. a costume designer, my job is to make special clothes ______ the measure of all cast in the film.[ ]A.forB.accordingC.toD.by

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• [单选题]下列命题正确的是A.若两条直线与同一个平面所成的角相等,则这两条直线平行B.若一条直线垂直于一个平面内的两条直线,则这条直线垂直于这个平面C.若一条直线平行于两个相交平面,则这条直线与这两个平面的交线平行D.若两个平面都垂直于第三个平面,则这两个平面平行

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• [单选题]已知p:0＜x＜21,则p是q的[ ]A.充分不必要条件B.必要不充分条件C.充要条件D.既不充分也不必要条件

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• [单选题]Poor health does not rule out happiness except for the ______ or those in pain.A.severely weakeningB.having severely weakenedC.severely weakenedD.being severely weakened

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• [单选题]________you can pass the exam or not depends on yourself.A.WhatB.ThatC.HowD.Whether

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