两个波在一很长的弦线上传播。设其波动表式为[tex=14.286x2.143]YcGBtSb0n2QQNZ8br8RFjE9H9cQX3e3cDPHV/pk07T6iMt1HeLYyZxDmkJtGIvW0Qv+MX7okRJvYqFXDrX4KZg==[/tex] 单位[tex=0.429x1.357]plHcCtdncEdTzaEI1WHBQA==[/tex][tex=14.429x2.143]GK8CEH4zweU5P6xLHYIfimjt7FKRoJs2wdn77otRod/3o2h/onKq3KG0LbiPXXGH5ZWmsDo37+ZmP2Cmk7gxstkYCWcFLxL8+kDiqy4dVyQ=[/tex]单位[tex=0.429x1.357]plHcCtdncEdTzaEI1WHBQA==[/tex]求: 合成波的表达式;

所有形为[tex=3.071x2.5]JfuQnY9G7d3YES/K7AC/I2A53l2IzXDk8Cyn7ibp0vEBgU+NrETNaIWu9bnVDwKa[/tex][tex=4.643x1.357]CWbNHt7uwvFZABShrf5s/H+Yaw3gaTdHYZXza8Z41mQ=[/tex] 皆为复数[tex=0.429x1.357]plHcCtdncEdTzaEI1WHBQA==[/tex]的矩阵对于矩阵的乘法成为一个群.

判断下列函数式是连续时间信号还是离散时间信号, 若是离散信号 是否为数字信号?[tex=3.786x1.357]oKyoV657rWrrU/VPd9xRZ1jQKwF2c1gXZro/D6YwXIM=[/tex] [tex=1.429x1.357]t1GRzLR2lCNCiG4l4bRiw8OSCJM5erKtoX+pQ9kC6uc=[/tex] 为任意值[tex=0.429x1.357]plHcCtdncEdTzaEI1WHBQA==[/tex]， [tex=0.643x0.786]/he/ol8BkDuTTL9yMPtH4Q==[/tex] 为正整数

设[tex=0.786x1.0]AOSTmhvIsOwsdZlGoks7dg==[/tex]是一个[tex=1.786x1.5]lki8otCS5SNtN16/lD2WJA==[/tex]为素数[tex=0.429x1.357]plHcCtdncEdTzaEI1WHBQA==[/tex]阶环，证明：[tex=0.786x1.0]AOSTmhvIsOwsdZlGoks7dg==[/tex]是[tex=2.214x1.143]NEBgiu4e3l8sh2J/FczUWg==[/tex]环[tex=2.857x1.286]6f+P4CIy45aab8A5ZwLRxxUgrz8yTVA+e72Z+Rfd4GQ=[/tex]是域或[tex=5.429x1.571]1tb8Q3/xue+tNNG+QJ8LiKbBpBdoaYVt6J/LI5ah5zg=[/tex].

一理想气体经图示各过程,试讨论其摩尔热容的正负 : [tex=1.286x1.357]utHvH4igaptAEXsEZc1Kjw==[/tex]过程 [tex=1.786x1.143]3FOnLdBsdukwCin9TexP1Q==[/tex]; [tex=1.286x1.357]BEB68bP4vOVk/XYYizw11w==[/tex]过程 [tex=2.429x1.429]rDpVENpJk65pskdLmqU/1JnJIh01yA767fnQZVT8cl4=[/tex]沿绝热线[tex=0.429x1.357]plHcCtdncEdTzaEI1WHBQA==[/tex];[tex=1.286x1.357]H6tHfFjOZ3ZWdB4qPQ9Ocg==[/tex]过程[tex=2.214x1.286]6RvWhwBg+vr9xjd67/2+aWQmorLjomcEGiPDUykc6pA=[/tex] 。[img=283x242]1796f46e8396702.png[/img]

适当选取坐标系，求轨迹的方程：求与二给定直线等距离的点轨迹的方程，已知二直线之间的距离为 [tex=0.571x0.786]HXNXn3AXpwdIpZt8+6oCEw==[/tex]，夹角为[tex=0.929x1.357]IMwSIRdPCLXWiDHw1lQZmQ==[/tex]取公垂线为[tex=0.5x0.786]C7x+w8+jOPZzxFrGGne6Dw==[/tex]轴，中点为原点，[tex=0.857x1.0]KGogyvwDAIJf/iL0H/9wjg==[/tex]轴与二直线成等角[tex=0.429x1.357]plHcCtdncEdTzaEI1WHBQA==[/tex]。

图[tex=2.286x1.143]Y1RwyYnlx+H2JE1znvVUgA==[/tex]所示的滚子摆动从动件盘形凸轮机构,凸轮廓线为一偏心圆。试在图上标出凸轮在 [tex=0.714x1.0]YiLkHgl7MlxE+QjUplQUKA==[/tex] 点接触时凸轮机构的压力角[tex=1.0x1.0]ux5iAn07xswc7bL3E9AKUw==[/tex]及从动件升程角 [tex=1.429x1.357]3XOffRs8GiA77HZ/kpscDA==[/tex] 角位移[tex=0.429x1.357]plHcCtdncEdTzaEI1WHBQA==[/tex]。[img=334x245]179b83da9000bc1.png[/img]

for i in range(b.max_row): for j in range(b.max_column): print(b.cell(row=i,column=j).value)上面语句运行的结果是：__________。 A: 1 1 1 1 1 1 1 1 1 1 B: 1111111111 C: 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 D: 出现异常

【单选题】CDMA通信的基站,假定基站A的码片序列是+1 +1 +1 -1 -1 +1 -1 -1,基站发射bit为101时,实际发射的信号是 A. +1 +1 +1 -1 -1 +1 -1 -1 +1 +1 +1 -1 -1 +1 -1 -1 –1 –1 –1 +1 +1 –1 +1 +1 B. +1 +1 +1 -1 -1 +1 -1 -1 –1 –1 –1 +1 +1 –1 +1 +1 +1 +1 +1 -1 -1 +1 -1 -1 C. +1 +1 +1 -1 -1 +1 -1 -1 +1 +1 +1 -1 -1 +1 -1 -1 +1 +1 +1 -1 -1 +1 -1 -1 D. –1 –1 –1 +1 +1 –1 +1 +1 –1 –1 –1 +1 +1 –1 +1 +1 –1 –1 –1 +1 +1 –1 +1 +1

for i in range(1,11): for j in range(1,11): b.cell(row=i,column=j).value=1 #b是一个工作表对象for i in range(1,11): for j in range(1,11): print(b.cell(row=i,column=j).value,end=" ") print()上面程序代码运行的结果是（）。 A: 1 B: 1 1 1 1 1 1 1 1 1 1 C: 1111111111 D: 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1