系统各项系数的符号必须大于零且a0a3＜a1a2是( )阶系统稳定的必要条件。 A 发布时间：2018-01-29 08:54 │ 来源：www.tikuol.com 题型：单项选择题 问题： 系统各项系数的符号必须大于零且a0a3＜a1a2是( )阶系统稳定的必要条件。A．1 B．2 C．3 D．4．
题型：单项选择题 完成对话，把正确选项的字母代号写在横线上。A. That sounds good.B. I have a TV set.C. Where is it?D. I don't have a computer.E. Great. Let's play it.Bob: Let's play computer games.Tony: 1 Where is your computer?Bob: 2 Do you have one?Tony: No, I don't. 3 Let's watch TV.Bob: No, it's boring. Let's play tennis. I have a tennis racket.Tony: Good. 4 Bob: On the sofa. Do you have a racket?Tony: No, I don't. But your sister has one.Bob: That's right. And she has a tennis ball.Tony: 5 查看答案