[单选题]已知P是边长为2的正△ABC边BC上的动点,则A.最大值为8B.是定值6C.最小值为2 D.与P的位置有关
[单选题]I have had my bike _____, and Im going to have somebody______ my radio tomorrow.A.repair; to repairB.repairing; to be repairedC.repaired; repairD.to repair; repairing
[单选题]In the end, it was Becky ________ he turned for a gentle word and a smile.[ ]A. on whomB. in whomC. to whomD. for whom
[单选题]已知集合A.数集,则“A∩{0,l}={0}”是“A={0}”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
[单选题]已知命题p:vx1:x2∈R[f(x2)-f(x1)(x2-x2)≥0,则命题p的否定是A.3x1,x2∈R[f(x2)-f(x1)](x2-x1)≤0B.3x1:x2∈RL(x2)-f(x1)(x2-x2)<0C.vx1:x2∈R,Lf(x2)-f(x1)](x2-x1)≤0D.Vx1,x2∈R,[f(x2)-f(x1)](x2-x2)<0
[单选题]Sometimes proper answers are not far to seek________food safety problems.[ ]A. inB. toC. onD. after
[单选题]Students in that school are judged ________what they have achieved in their studies. [ ]A. in spite ofB. in charge ofC. in favor ofD. in terms of
[单选题]记实数x1,x2,……,xn中的最大数为max{x1,x2,……,xn},最小数为min{x1,x2,……,xn}.已知△A.C的三边长为a,b,c(a≤b≤c),定义它的倾斜度为“l=max{}·min{},则“l=1”是“△ABC为等边三角形”的 [ ]A.必要而不充分的条件B.充分而不必要的条件C.充要条件 D.既不充分也不必要条件
[单选题]Teenagers ______ social experience, so they are easily ______ when they first step into society.A.lack; taken upB.lacking in; taken overC.a lack of; taken onD.lack; taken in
[单选题]When Richard said,“You are much more agreeable and prettier now,Joan’s face turned red at the unexpected_____.A.commandB.comparisonC.complimentD.contribution
[计算题]已知向量a=(3sin 2x, cos 2x), b=(cos 2x, -cos 2x.(Ⅰ)若7丌5丌x∈24P2a2b+2=5求cos4x;(Ⅱ)设△ABC的三边a,b,c满足b2=ac,且边b所对应的角为x,若关于x的方程ab+-=mm有且仅有一个实数根,求m的值.
[单选题]The same gestures, signs and so on, in other words, body language, may express different ideas or meanings in different cultures, so dont use them _______ you are definitely sure of what they meanso as to reduce misunderstanding ______ the smallest number. [ ]A. until; withB. unless; toC. until; by D. unless; by
[单选题]Nowadays, China has become the largest consumer of mobile phones. _______, every person has one mobile phone.A.Above allB.In other wordsC.On the wholeD.On average
[单选题]— How did they get to know each other—The Chinese skier made the of the Canadian player at 2014 Sochi Winter Olympic Games.A.acquaintanceB.achievementC.decisionD.investigation
[单选题]________ your major, youll have to take general education classes in your first two years of college.[ ]A. In spiteB. No matterC. Regardless ofD. With regard to
[单选题]Rather than ________at home watching TV, Id prefer_______in the office.A.working...stayingB.working...stayC.to work...stayD.work...to stay
[单选题]若向量a=(x,3)(x∈R),则“x=4”是“|a|=5”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.既不充分又不必要条件
[单选题]设命题甲为“a,b,c成等差数列”,命题乙为“”,那么[ ]A.甲是乙的充分不必要条件 B.甲是乙的必要不充分条件C.甲是乙的充要条件D.甲是乙的既不充分也不必要条件
[单选题]The story of Whitney Houston is a good example of how drugs and bad relationships can _______ even the most talented stars.?A.murderB.presentC.ruinD.suspect
[单选题]His son is addicted________ detective novels. [ ]A. to reading B. to readC. in read D. in reading
[单选题]Today the Red Cross provides a number of services for the public, such as helping people________, teaching first aid and providing blood.A.in needB.in returnC.in preparationD.in anger