问答题将展开成x的幂级数．

问答题计算，[x]表示不超过x的最大整数．

问答题证明方程2x=x2+1有且仅有三个实根．

问答题{{B}}Directions:{{/B}} Read the following passage carefully and then translate each underlined part into Chinese.71.{{U}}The international software market represents a significant business opportunity for U.S. microcomputer software companies, but illegal copying of programs is limiting the growth of sales abroad. If not dealt with quickly, international piracy of software could become one of the most serious trade problems faced by the United States{{/U}}. 72. {{U}}Software piracy is already the biggest barrier to U.S. software companies entering foreign markets. One reason is that software is extremely easy and inexpensive to duplicate compared to the cost of developing and marketing the software. The actual cost of duplicating a software program, which may have a retail value of $ 400 or more, can be as little as a dollar or two—the main component being the cost of the diskette{{/U}}. 73. {{U}}The cost of counterfeiting software is substantially less than the cost of duplicating watches, books, or blue jeans. Given that the difference between the true value of the original and the cost of the counterfeit is so great for software, international piracy has become big business. Unfortunately, many foreign governments view software piracy as an industry in and of itself and look tile other way{{/U}}. U.S. firms stand to lose million of dollars in new business, and diminished U.S. sales nut only harm individual firms but also adversely affect the entire U.S. economy.

问答题设A为3阶矩阵，α1，α2，α3是线性无关的3维列向量，且Aα1=α2-α3，Aα2=3α1-2α2+α3，Aα3=3α1+2α2-3α3．

问答题试给出函数y=f(x)的图像关于直线x=a对称的充要条件．

问答题已知随机变量(X，Y)的概率密度为(Ⅰ)求常数A；(Ⅱ)求条件概率密度fY|X(y|x)．

问答题求

问答题设a0=1，，(n≥0)(Ⅰ)证明：当|x|＜1时，幂级数收敛；(Ⅱ)求该幂级数的和函数S(x)．

问答题计算二重积分

问答题计算．