学科分类

已选分类 理学数学基础数学
单选题设x>0处f(x)连续且严格单调增,并设,则F(x)在x>0处().
进入题库练习
单选题设矩阵A的伴随矩阵,且ABA-1=BA-1+3E,其中E为四阶单位矩阵,则矩阵B为______A.B.C.D.
进入题库练习
单选题设X1,X2,…,Xn(n>2)为来自总体N(0,1)的简单随机样本,为样本均值.记Yi=,i=1,2,…,n.则______A.B.C.D.
进入题库练习
单选题已知x,y,z为两两不相等的三个实数,且,则x2y2z2的值为______.
进入题库练习
单选题由数字1,2,3,4,5组成没有重复数字且数字1与2不相邻的五位数有( )
进入题库练习
单选题某计算机用户计划使用不超过500元的资金购买单价分别为60元、70元的单片软件和盒装磁盘,根据需要,软件至少买3片,磁盘至少买2盒,则不同的选购方式共有( )种.
进入题库练习
单选题a,b是均小于10的自然数,且a与b之比是一个既约的真分数,而b的倒数等于,则是().
进入题库练习
单选题若正数a、b满足ab=a+b+3,则ab的取值范围是( )。
进入题库练习
单选题
进入题库练习
单选题某城市计划从今年开始经过两年的时间,将城市绿地面积从今年的144万平方米提高到225万平方米,则每年平均增长( ).
进入题库练习
单选题设函数f(x)=cos(x+y),则等于
进入题库练习
单选题设f(x)是可导的连续函数,则等于______.A.f(3)-f(1)B.f(9)-f(3)C.D.
进入题库练习
单选题设f(x)的定义域是[-1,0],的定义域是()。
进入题库练习
单选题If the opinion polls are to be believed, most Americans are coming to trust their government more than they used to. The habit has not yet spread widely among American Indians, who suspect an organization which has so often patronized them, lied to them and defrauded them. But the Indians may soon win a victory in a legal battle that epitomizes those abuses. Elouise Cobell, a banker who also happens to be a member of the Blackfeet tribe in Montana, is the leading plaintiff in a massive class-action suit against the government. At issue is up to $10 billion in trust payments owed to some 500,000 Indians. The suit revolves around Individual Indian Money (11M) accounts that are administered by the Interior Department's Bureau of Indian Affairs (BIA). Back in the 1880s, the government divided more than 11m acres of tribal land into parcels of 80 to 160 acres that were assigned to individual Indians. Because these parcels were rarely occupied by their new owners, the government assumed responsibility for managing them. As the Indians' trustee, it leased the land out for grazing, logging, mining and oil drilling--but it was supposed to distribute the royalties to the Indian owners. In fact, officials admit that royalties have been lost or stolen. Records were destroyed, and the government lost track of which Indians owned what land. The plaintiffs say that money is owing to 500,000 Indians, but even the government accepts a figure of about 300,000. For years, Cobell heard Indians complain of not getting payment from the government for the oil-drilling and ranching leases on their land. But nothing much got done. She returned to Washington and, after a brush-off from government lawyers, filed the suit. Gale Norton, George Bush's interior secretary was charged with contempt in November because her department had failed to fix the problem. In December, Judge Lam berth ordered the interior Department to shut down all its computers for ten weeks because trust-fund records were vulnerable to hackers. The system was partly restored last month and payments to some Indians, which had been interrupted l resumed. And that is not the end of it. Ms Norton has proposed the creation of a new Bureau of Indian Trust Management, separate from the BIA. Indians are cross that she suggested this without consulting them. Some want the trust funds to be placed in receivership, under a , neutral supervisor. Others have called for Congress to establish an independent commission, including Indians, to draw up a plan for reforming the whole system. A messy injustice may at last be getting sorted out.
进入题库练习
单选题下列不定积分计算正确的是A.∫x2dx=x3+CB.C.∫sinxdx=cosx+CD.∫cosxdx=sinx+C
进入题库练习
单选题关于x的方程k2x2+(2k-1)x+1=0有实数根,则下列说法正确的是______。A.当时方程两根互为相反数B.当k=0时方程的根是x=-1C.当k=±1时方程两根互为倒数D.当时方程有实数根
进入题库练习
单选题则n的最小值为()。
进入题库练习
单选题级数(k为非零常数)______
进入题库练习
单选题设函数f(x)=e x lnx,则f"(1)=
进入题库练习
单选题当x=时,3(x+5)(x-3)-5(x-2)(x+3)的值等于().
进入题库练习