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#1 2014-03-15 04:03:43

gourish
Member
Registered: 2013-05-28
Posts: 153

the complex plane- my tragedy

if z=2+ia y=b+i2 x=0 are vertices of an equilateral triangle such that a, b are
real numbers such that a, b ∈(0,1) then which of the following is true?

1.)a=b=4+2sqrt(3)
2.)a=2, b=sqrt(3)
3.)a=sqrt(3),b=2
4.)a=b=-1+sqrt(2)

i found that a=b=4+2sqrt(3) or 4-2sqrt(3) but due to the condition a,b ∈(0,1) i choose  4-2sqrt(3) but it's not even in the options the answer sheet says that the right answer is 4.)
why is it so?can anybody please help me out on this one


"The man was just too bored so he invented maths for fun"
-some wise guy

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#2 2014-03-15 04:35:28

Bob
Administrator
Registered: 2010-06-20
Posts: 10,053

Re: the complex plane- my tragedy

hi gourish

I'm getting the same result as you.

I wonder if there's a typo with the question, because 3 answers can be rejected without calculation, just using a, b in (0,1).

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#3 2014-03-15 04:48:00

gourish
Member
Registered: 2013-05-28
Posts: 153

Re: the complex plane- my tragedy

thanks good to know that.... smile


"The man was just too bored so he invented maths for fun"
-some wise guy

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#4 2014-03-15 04:53:32

Bob
Administrator
Registered: 2010-06-20
Posts: 10,053

Re: the complex plane- my tragedy

Hi

Did you follow what Nehushtan said about the integration question?

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#5 2014-03-15 04:56:23

gourish
Member
Registered: 2013-05-28
Posts: 153

Re: the complex plane- my tragedy

no, i did not know can you send me the link?


"The man was just too bored so he invented maths for fun"
-some wise guy

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#6 2014-03-15 04:58:17

Bob
Administrator
Registered: 2010-06-20
Posts: 10,053

Re: the complex plane- my tragedy


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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