填空题 将适当的函数填入下列括号内，使等式成立：

填空题∫(arcsinx) 2 dx=____________.

填空题设X，Y相互独立且都服从标准正态分布，则E|X-Y|=______，D|X-Y|=______．

填空题Scholars, writers and teachers in the modern academic community have strong feelings about acknowledging the use of another person's ideas. In the English-speaking world, the term plagiarism is used to label the practice of not giving credit for the source of one's ideas. 41．______ 42．______In many universities, the punishment may range from failure in a particular course to expulsion from the university. In the literary world, where writers are protected from plagiarism by international copyright laws, the penalty may range from a small fine to imprisonment and a ruined career. Protection of scholars and writers, through the copyright laws and through the social pressures of the academic and literary communities, is a relatively recent concept. Such social pressures and copyright laws require writers to give scrupulous attention to documentation of their sources. Students, as inexperienced scholars themselves, must avoid various types of plagiarism by being self-critical in their use of other scholars' ideas and by giving appropriate credit for the source of borrowed ideas and words, otherwise dire consequences may occur. 43．______ Plagiarism by accident, or oversight, sometimes is the result of the writer's inability to decide or remember where the idea came from. He may have read it long ago, heard it in a lecture since forgotten, or acquired it second-hand or third-hand from discussions with colleagues. He may also have difficulty in deciding whether the idea is such common knowledge that no reference to the original source is needed. Although this type of plagiarism must be guarded against, it is the least serious and, if lessons learned, can be exempt from being severely punished. Plagiarism through ignorance is simply a way of saying that inexperienced writers often do not know how or when to acknowledge their sources. The techniques for documentation-note- taking, quoting, footnoting, listing bibliography-are easily learned and can prevent the writer from making unknowing mistakes or omissions in his references. 44．______ The most serious kind of academic thievery is plagiarism by intention. The writer, limited by his laziness and dullness, copies the thoughts and language of others and claims them for his own. He not only steals, he tries to deceive the reader into believing the ideas are original. Such words as immoral, dishonest, offensive, and despicable are used to describe the practice of plagiarism by intention. The opposite of plagiarism is acknowledgement. 45．______Students, as developing scholars, writers, teachers, and professional leaders, should recognize and assume their responsibility to document all sources from which language and thoughts are borrowed. Other members of the profession will not only respect the scholarship, they will admire the humility and honesty. [A] The penalties for plagiarism vary from situation to situation. [B] Many scholars suggest rigid self-regulations in academic world in order to protect the purity of academics. [C] "Penalty for plagiarism should be regulated by laws and regulations," said one scholar, "it is no better than theft. " [D] Although there is no copyright in news, or in ideas, only in the expression of them, the writer cannot plead ignorance when his sources for ideas are challenged. [E] Simply stated, plagiarism is "the wrongful appropriation or purloining, and publication as one's own of the ideas, or the expression of ideas of another. " [F] All mature and trustworthy writers make use of the ideas of others but they are careful to acknowledge their indebtedness to their sources. [G] There are at least three classifications of plagiarism as it is revealed in students' inexactness in identifying sources properly. They are plagiarism by accident, by ignorance, and by intention.

填空题设α=(1，3，-2) T ，β=(2，0，0) T ，A=αβ T ，则A 3 =______．

填空题 设z=x4+2y2，则dz=______．

填空题设则fn(x)=________.

填空题微分方程(2x+3)y"=4y"的通解为______．

填空题累次积分=________．

填空题设A为三阶矩阵，A的各行元素之和为4，则A有特征值______，对应的特征向量为______．

填空题设区域D为x2+y2≤R2，则

填空题设A，B均是n阶对称矩阵，则AB是对称矩阵的充要条件是____．

填空题设f(x，y)满足，f(x，0)=1，f"y(x，0)=x，则f(x，y)=________．

填空题设a，b，a+b均非0，则行列式=________

填空题以成本价为衡量标准，某商品按6折出售可获利5%． (1)该商品按7折出售可获利10%； (2)该商品按原价出售可获利75%．

填空题 以为根的有理系数不可约多项式_________.

填空题交换积分次序：=________

填空题y"+y"=xe -x 的通解是______．

填空题设，则a=________．

填空题袋中有8个球，其中有3个白球，5个黑球，从中随意取出4个球，如果4个球中有2个白球2个黑球，试验停止，否则将4个球放回袋中重新抽取4个球，直至取到2个白球2个黑球为止．用X表示抽取次数，则PX=k=______(k=1，2，…)，EX=______．