问题 填空题
下面有4个关于复数的类比推理:
①复数的加减运算可以类比多项式的加减运算;
②由向量
a
的性质|
a
|2=
a
2
类比复数z的性质|z|2=z2
③由向量的性质|
a
+
b
|≤|
a
|+|
b
|
可以类比得到复数z1、z2满足|z1+z2|≤|z1|+|z2|;
④由向量加法的几何意义可以类比得到复数加法的几何意义.
其中结论正确的是______.(写出所有符合要求的序号)
答案

复数的加减法运算可以类比多项式的加减法运算法则,①正确

由向量的性质|

a
|2=
a
2
类比得到复数z的性质|z|2=z2,这两个长度的求法不是通过类比得到的.故②不正确,

由向量三角不等式可以类比得到复数三角不等式.故③正确.

由向量加法的几何意义可以类比得到复数加法的几何意义.故④正确.

故答案为:①③④.

阅读理解

阅读理解

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1. How can LightSleeper help a person fall asleep?

A. Its light makes people feel calm.

B. It doesn't make any noise.

C. It is fixed on the ceiling.

D. Its light moves fast.

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