Author Topic: Some math help.  (Read 1158 times)

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Offline iDante

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Some math help.
« on: March 16, 2009, 03:58:52 am »
So my math teacher gave us some extra credit. The problem is this:
Code: [Select]
x^3 - 1 = 0
x^6 - 1 = 0
x^12 - 1 = 0
Solve for all (real and imaginary) values of x
I promptly factored/solved them and showed him my answers. He said, "What you did is correct, but this can also involve trigonometry and there should be a picture involved." So I need to show him that to get the extra credit.

The answers to the first one (x^3 - 1 = 0) are this btw, if it helps:
Code: [Select]
x = {1, (-1/2) + (sqrt(3)/2)i, (-1/2) - (sqrt(3)/2)i }
Any help is much appreciated, as I have no idea what he's going on about.

Offline N. Escalona

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Re: Some math help.
« Reply #1 on: March 16, 2009, 04:59:34 am »
solved on IRC, topic can be locked AFAIK
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Offline ~Niko~

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Re: Some math help.
« Reply #2 on: March 16, 2009, 09:34:36 am »
Im doing that kind of stuff at shool too :)

Offline Sir Jeremy

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Re: Some math help.
« Reply #3 on: March 16, 2009, 01:16:45 pm »
I am not.  Thank God.  Looks fairly complicated.  Luckily I'm still in easy algebra. <3

Offline N. Escalona

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Re: Some math help.
« Reply #4 on: March 16, 2009, 01:52:24 pm »
If anyone's curious, the answer is the nth roots of unity. Look it up on Wikipedia or Mathworld.
Do you want to see me crawl across the floor to you?
Do you want to hear me beg you to take me back?
I'd gladly do it because
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Offline ~Niko~

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Re: Some math help.
« Reply #5 on: March 16, 2009, 04:08:27 pm »
I am not.  Thank God.  Looks fairly complicated.  Luckily I'm still in easy algebra. <3
it's not complicated. I do them as if they would be sums :)

Offline blackdevil0742

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Re: Some math help.
« Reply #6 on: March 16, 2009, 06:23:00 pm »
sigh. I used to be good at these but 1.5 years without math... can't even remember anything anymore.

OBEY!!!

Offline LtKillroy

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Re: Some math help.
« Reply #7 on: March 16, 2009, 06:52:25 pm »
I have a calculator that does that for me. It makes it easier.
L'audace, l'audace, toujours l'audace

Offline iDante

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Re: Some math help.
« Reply #8 on: March 16, 2009, 07:19:32 pm »
Actually it is pretty complicated. Finding the answers is easy, as LtKillroy said you can just plug it into a TI-89 and it spits out the answers.

But it turns out that when you get things with x^n = 1 then interesting things happen.
If anyone's curious, the answer is the nth roots of unity. Look it up on Wikipedia or Mathworld.

(this can be locked thanks people)

Offline a-4-year-old

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Re: Some math help.
« Reply #9 on: March 16, 2009, 07:21:16 pm »
I have a calculator that does that for me. It makes it easier.
When you get a test that doesn't allow calculators then you're boned
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Offline The Geologist

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Re: Some math help.
« Reply #10 on: March 16, 2009, 09:57:35 pm »
Locked :D
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