单选题设常数a，b满足则A．B．C．D．

单选题设为可逆矩阵，，又则B-1=(A)P2A-1P4．(B)A-1P2P3．(C)P1P3A-1．(D)P4P1A-1．

单选题设，，则当x→0时，f(x)是g(x)的______．

单选题曲线y=x 2 与曲线y=alnx(a≠0)相切，则a=

单选题设f(x)在(-∞，+∞)有连续的二阶导数且满足：f(x+h)+f(x-h)=，则

单选题设n阶矩阵A=(α 1 ，α 2 ，…，α n )，B=(β 1 ，β 2 ，…，β n )，AB=(γ 1 ，γ 2 ，γ n )， 令向量组(Ⅰ)：α 1 ，α 2 ，…，α n ；(Ⅱ)：β 1 ，β 2 ，…，β n ；(Ⅲ)：γ 1 ，γ 2 ，…，γ n ，若向量(Ⅲ)线性相关，则______．

单选题Henry Kissinger may be the most successful, certainly the most flamboyant, Secretary of State to hold that office in modern times. When he was appointed in the late 1960's, there were no American ties with Communist China, Vietnam and Berlin seemed ready to draw the United States into a third world war, and Russia was seen as "the enemy". But all this has changed, and Henry Kissinger caused much of the change; in 1971, he made his first trip to China, a trip that was the beginning of the current ties between the United States and China. He brought the United States and Russia closer together on major issues by the policy he called "detente", literally meaning a relaxation. His philosophy was always to talk and to bring together. With these two policies, Kissinger did much to draw attention away from any possible Russia-American friction. In 1973 he made his first visit to Egypt. Here he was able to begin U.S. relations with Egypt. He used his contact later to begin the sort of talks that the American press called "shuttle diplomacy". For ninety-nine days, he "shuttled" back and forth on flights between Cairo and Jerusalem to work out a step-by-step withdrawal of Israeli troops from the Sinai desert. His wit, his careful approach to detail, and his presence made "shuttle diplomacy" work. It was the only successful approach to Mid-east peace in the thirty years since the state of Israel was founded. Another major work was the Strategic Arms Limitation Talk. Though his term in office passed with the treaty unsigned, Kissinger left a draft of the treaty to which the Russians had already agreed. The SALT treaty spelled out a one-tenth reduction in nuclear arms, a major accomplishment by any standard, even if one does not consider all the other conditions and limitations included in the treaty. Even though he successfully helped bring an end to the Vietnam War, Kissinger's final days in office were affected, as was the entire executive branch in one way or another, by the scandals of the Nixon White House. Kissinger's critics point to his role in placing wiretaps on the phones of reporters and officials and to what they consider his "high-handed" approach to setting foreign policy. But Kissinger, during the last few months of the Nixon presidency, limited the effects of American domestic problems on our foreign policy. He continued talks in the Middle East. He continued close contact with the Soviet Union. History will decide in the final view, as Kissinger--and many presidents--often said, on the value of his service. Whatever they decide, whether his actions are finally to be considered wise or foolish, he had a personal vision that will be difficult to match. (459 words)Notes: work out 制定。spell out 清楚地说明。wiretap 窃听(电话)。scandal 丑闻。