一、选择题(每题3分。请将答案的序号填入划线内) 1.正方体仅受两个力偶作用,该两力偶矩矢等值、反向,即M1=M2,但不共线,则正方体 ①平衡; ②不平衡; ③因条件不足,难以判断是否平衡

4.0引言 一、决策问题的表格表示损失矩阵对无观察(No-data)问题a= 可用表格(损失矩阵)替代决策树来描述决策问题的后果(损失):

一、解答下列各题(本大题共3小题,总计13分) 1、(本小题4分) 对函数f(x)= arctan在[0,1]上验证拉格朗日中值定理的正确性

一、质点和质点系的动量 1.质点的动量 p =mv质点机械运动的量度 2.质点系的动量 N个质量分别为m1,m2,…,m,动量分别为P1,P2,,PN的质点组成质点系,其总动量为

Home Study Exercise (E1)O&W3.46(a)and(c) (t) and y(t) are continuous-time periodic signals with a period= To and Fourier series representations given b

Last time: Unit circle (=1) in the ROCDTFT X(@) exists Rational transforms correspond to signals that are linear combinations of DT exponentials

Another(important! ) example: Periodic Impulse train n(t)=∑(t Sampling function important for sampling .2T

一、(10分)已知某连续时间信号如图所 x()示。 1.绘出信号x1()=x(4--)的波形; 2若x(t)的频谱是X(),试用X()表

一、判断下列说法是否正确,用“√”或“”表示判断结果。 (1)在图T8.1所示方框图中,若中F180°,则只有当中A=±180°时,电路才能产生正弦波振荡。()

Through the study of these two periods of class, the students should understand the text correctly. The new words should be read fluently. The w = new words and the expressions in the text should be learnt by heart