Re: Sqrt of complex number
- To: mathgroup at smc.vnet.net
- Subject: [mg126642] Re: Sqrt of complex number
- From: "Dave Snead" <dsnead6 at charter.net>
- Date: Mon, 28 May 2012 05:10:39 -0400 (EDT)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- References: <201205270842.EAA17817@smc.vnet.net>
Use Solve to get both answers:
Solve[z^2==3-4I,z]
{{z->-2+I},{z->2-I}}
Cheers,
Dave Snead
-----Original Message-----
From: Jacare Omoplata
Sent: Sunday, May 27, 2012 1:42 AM
To: mathgroup at smc.vnet.net
Subject: [mg126642] Sqrt of complex number
Hi,
When I try to find the square root of of a complex number, I get only one
answer.
In[1]:= Sqrt[3-4 I]
Out[1]= 2-I
But -2+I is an answer as well.
In[2]:= (-2+I)^2
Out[2]= 3-4 I
Why does Mathematica give the first answer and not the second? Does it
choose the answer with the positive real number? Is there any way I can get
both answers? Or do I just have to remember that the negative of the given
answer is also an answer?
Thanks.
- References:
- Sqrt of complex number
- From: Jacare Omoplata <walkeystalkey@gmail.com>
- Sqrt of complex number