Forgot password
 Register account
View 316|Reply 7

[函数] 复数根号(-1)=i的表述对吗?

[Copy link]

205

Threads

263

Posts

1

Reputation

Show all posts

hjfmhh posted 2024-2-8 15:28 |Read mode
复数根号(-1)=i的表述对吗?

281

Threads

550

Posts

2

Reputation

Show all posts

力工 posted 2024-2-8 20:11
是这样的式子$\sqrt[i]{-1}$?

24

Threads

1014

Posts

46

Reputation

Show all posts

战巡 posted 2024-2-9 14:47
基本没问题,许多数学教材和学术论文文献里面,都是直接写$\sqrt{-1}=i$的

3200

Threads

7827

Posts

52

Reputation

Show all posts

hbghlyj posted 2024-2-10 01:02
力工 发表于 2024-2-8 12:11
是这样的式子$\sqrt[i]{-1}$?
$\sqrt[i]{-1}=e^π$

Comment

应该直接说是根号-1=i,错误地以为是。。。,觉得定义为=-i也是可以的,体现出共轭  posted 2024-2-10 12:23

764

Threads

4672

Posts

27

Reputation

Show all posts

isee posted 2024-2-10 20:40
Last edited by isee 2024-2-10 20:47人教群有人问过,我觉得在不引起误会的情况下是可以的.

不过,不推荐,这种记号不严谨.

对于虚数单位 $\mathrm i%$,其满足二者:
(1) $\mathrm i^2=-1$.
(2) 实数与 $\mathrm i%$ 可以进行四则运算,且原来加,乘运算律仍然成立.

这样就是虚数单位的定义了.

若不然,就会有逻辑错误式,如\[1=\sqrt{-1\cdot(-1})=\mathrm i\cdot \mathrm i=-1,\]这就很荒谬了.

Comment

明显1#就是人教群那位  posted 2024-2-10 21:30
isee=freeMaths@知乎

3200

Threads

7827

Posts

52

Reputation

Show all posts

hbghlyj posted 2024-3-20 23:58
Desmos不识别$\sqrt{-1}$,也不识别$i$,那怎么输入$i$呢?
Screenshot 2024-03-20 155639.png
Screenshot 2024-03-20 155857.png

Quick Reply

Advanced Mode
B Color Image Link Quote Code Smilies
You have to log in before you can reply Login | Register account

$\LaTeX$ formula tutorial

Mobile version

2025-7-15 14:14 GMT+8

Powered by Discuz!

Processed in 0.017411 seconds, 33 queries