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**dorez****Member**- Registered: 2006-01-29
- Posts: 4

Asalam O ALikum,

Straight forward --> having problems understanding following questions....

1. If X & Y are two sets & n(X) =18,n(Y)=24, n(XUY)=40 then n(X[Intersection sign]Y)=

Answer is 2 but dont know how....

2. If x^2 +y^2 = a^2 then in terms of conjgate coordinates,____

Answers is Z.Z^_ = a^2 don't know how(meaning a __ above Z)

3. IF X=[1,4] & A=[2,4] then A' =

4. IF A[1,2] & B=(0,2) then A(Intersection Sign)B=

5. If i^2=-1, then the value of i^-4k+3

6. if a+i3b= -1+3i^2k then real part =_________

7. if x+iy=5-6i^2k, the imaginary part(y) =________

8. The expression of 3/(under-the-root->6) - (under-the-root->-12) in the form of a+ib is_________

Answer-> 1/(under-root->6) + i/under-root-3

More question relating complex numbers would be coming soon

If anyone else has a question to ask can also post here....

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**kempos****Member**- Registered: 2006-01-07
- Posts: 77

n(AUB)=n(A) + n(B) - n(AandB)

40 = 18+24 - n(AB)

n(AB) = 2

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**kempos****Member**- Registered: 2006-01-07
- Posts: 77

3. A` = [1,3] ?

4. [1,2)?

5. -i

*Last edited by kempos (2006-01-29 05:13:12)*

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**kempos****Member**- Registered: 2006-01-07
- Posts: 77

solved 8 but dont know how to put it here :-(

how to paste equation from MS word? i have saved this bloody thing as a jpg try to paste it here but it does not work :-(

*Last edited by kempos (2006-01-29 05:03:13)*

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**dorez****Member**- Registered: 2006-01-29
- Posts: 4

thanks kempos

can u also put in solution steps of 3,4,5 cause these questions are new to me....

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**kempos****Member**- Registered: 2006-01-07
- Posts: 77

i can't do it

do not know how to put it here :-(

5. i^(-4k+3) = i^-4k * i^3 = 1/i^4k * (-i) = 1/ i^2^2k * (-i) = 1/-1^2k * (-i) =

1/1^k *(-i) = 1*(-i) = -i

*Last edited by kempos (2006-01-29 05:11:36)*

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**kempos****Member**- Registered: 2006-01-07
- Posts: 77

what do you mean by A[0,2]?

*Last edited by kempos (2006-01-29 05:14:26)*

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**dorez****Member**- Registered: 2006-01-29
- Posts: 4

didn;t got u.....?

hmmm can u also give me solutions steps of 3 and 4 because haven't ever seen these type of questions before so ..... not sure about them.....

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**Kelp Kid****Member**- Registered: 2005-12-05
- Posts: 31

What on earth are you talking about?

Don't know don't care

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**dorez****Member**- Registered: 2006-01-29
- Posts: 4

i mean

how IF X=[1,4] & A=[2,4] then A' =3. A` =

Gives answer[1,3]

how IF A[1,2] & B0,2) then A(Intersection Sign)B=

Gives answer[1,2)

Also have another question

1. If the area of a triangle is 16, formed by the points Z, Z+iZ and iZ in a complex plane then |Z|=_____

Gives 4(Under-root-->2) how?

*Last edited by dorez (2006-01-29 22:14:38)*

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**Tigeree****Member**- Registered: 2005-11-19
- Posts: 13,883

don't bother Kelp Kid

*Last edited by Tiger (2006-01-30 19:17:04)*

People don't notice whether it's winter or summer when they're happy.

~ Anton Chekhov

Cheer up, emo kid.

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**kempos****Member**- Registered: 2006-01-07
- Posts: 77

is the question about the triangle correct? haveing some problems with it :-(

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**kempos****Member**- Registered: 2006-01-07
- Posts: 77

I'm getting 4sqrt2 but also imaginary numbers.

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**kempos****Member**- Registered: 2006-01-07
- Posts: 77

ok, got it. however difficult for me to expalin.

check:

http://regentsprep.org/Regents/mathb/3C6/absvlecomlesson.htm

not the sane problem but might help

*Last edited by kempos (2006-01-30 22:30:44)*

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**kempos****Member**- Registered: 2006-01-07
- Posts: 77

ok, here you go

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**Browniegirl32296****Member**- Registered: 2006-01-31
- Posts: 8

How do you get to be a full memeber? or how do you get those icons?

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**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,569

Hi Browniegirl ... welcome to the forum. Give people a little time to respond

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