Let

show that

I have tried to square the first equation and get,

and i can't seem to go any further from here, any help appreciated.

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- Nov 14th 2012, 02:51 AMTweetycomplex numbers, help
Let

show that

I have tried to square the first equation and get,

and i can't seem to go any further from here, any help appreciated. - Nov 14th 2012, 03:13 AMa tutorRe: complex numbers, help
It's true for all z.

- Nov 14th 2012, 03:38 AMTweetyRe: complex numbers, help
Okay, thank you,

I know

but i am not sure how to put this together to get - Nov 14th 2012, 05:49 AMa tutorRe: complex numbers, help
I hope your teacher set your task in writing. If so please post it exactly as it was given to you.

- Nov 14th 2012, 06:22 AMTweetyRe: complex numbers, help
Okay,

1) Z is the complex number

a) State the value of , hence show that for all

b) use the formula for the sum of a geometric series to show that

c) Let show that . Also show that and hence find an expression for in surd form.

i have done all parts except part c, am stuck on that bit

my solutons for a and b

recognising z as an 5th root of unity?

b)

- Nov 14th 2012, 06:48 AMPlatoRe: complex numbers, help
- Nov 14th 2012, 09:06 AMa tutorRe: complex numbers, help
In post 2 I meant it's NOT true for all z.

Sorry. - Nov 14th 2012, 09:36 AMTweetyRe: complex numbers, help
i am actually stil not able to compute part 'c'

- Nov 14th 2012, 09:59 AMPlatoRe: complex numbers, help
- Nov 14th 2012, 10:34 AMTweetyRe: complex numbers, help
- Nov 14th 2012, 10:50 AMPlatoRe: complex numbers, help
- Nov 14th 2012, 11:56 AMmathteacher067Re: complex numbers, help
Hello!

Would try to help you!

I'm not sure, but what i got is

Rectangualr form a^2*z^2+1/z^2+2

Polar form a^2*z^2+1/z^2+2

check it here Online Complex Numbers Calculator

I used Complex Numbers Calculator

Good luck