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#1 2008-08-07 03:38:35
- Daniel123
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- Registered: 2007-05-23
- Posts: 663
Cube roots of unity
This textbook is irritating me. What am I doing wrong?
If w is real, then w = 1, which gives
If w is complex, then w³ = 1, which gives
The book says the answer is w².
Thanks.
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#2 2008-08-07 03:51:08
- JaneFairfax
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- Registered: 2007-02-23
- Posts: 6,868
Re: Cube roots of unity
Last edited by JaneFairfax (2008-08-07 05:25:14)
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#3 2008-08-07 03:52:37
- Daniel123
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- Registered: 2007-05-23
- Posts: 663
Re: Cube roots of unity
Oops.... didn't notice that. But still, why hasn't the book mentioned '1' as an answer?
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#4 2008-08-07 03:53:48
- JaneFairfax
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- Registered: 2007-02-23
- Posts: 6,868
Re: Cube roots of unity
1 is one of the values of
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#5 2008-08-07 04:00:46
- Daniel123
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- Registered: 2007-05-23
- Posts: 663
Re: Cube roots of unity
Right, OK.
Trying to get back into maths after 4 weeks.
Thanks Jane.
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