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**RauLiTo****Member**- Registered: 2006-01-11
- Posts: 142

hello everybody ... in fact i dont know how to start

as you all know i am an arabian person ... i decided to make a topic in an arabic forum about math '' enjoy the math '' and i need some questions , tricks , math magic ... to put there so i need your help lovely members !!! who can give me links ? who can put questions not difficult ones but cool and nice question which make you interested in math !!!

thanks again

ImPo$$!BLe = NoTH!nG

Go DowN DeeP iNTo aNyTHinG U WiLL FinD MaTHeMaTiCs ...

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**RauLiTo****Member**- Registered: 2006-01-11
- Posts: 142

views : 16

replies : 0

...

ImPo$$!BLe = NoTH!nG

Go DowN DeeP iNTo aNyTHinG U WiLL FinD MaTHeMaTiCs ...

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**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,551

You could start with Add Two Numbers and the Answer is Always 1089

And then choose from Maths Puzzles and quizzes

And then onto Math and Logic Puzzles

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**Zhylliolom****Real Member**- Registered: 2005-09-05
- Posts: 412

You could always use my historical proof that *i[sup]i[/sup]* = *e[sup]-π*/2[/sup] ∈ **R**. I did it for a talent show and won, so I guess it could be used as good mathematical magic. It was a great day for mathematics. If you would like me to write out the problem, just ask.

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**Ricky****Moderator**- Registered: 2005-12-04
- Posts: 3,791

Zhylliolom, I get

, where n is an integer. Could I see your work?Interesting question though, I have to say.

"In the real world, this would be a problem. But in mathematics, we can just define a place where this problem doesn't exist. So we'll go ahead and do that now..."

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**Zhylliolom****Real Member**- Registered: 2005-09-05
- Posts: 412

Hopefully we all know Euler's formula:

For this problem, let 0 ≤ θ ≤ 2π. Now ask yourself, for what value of θ will *e[sup]i*θ[/sup] = *i*? Why yes, it's π/2!

So now we know that *e[sup]i*π/2[/sup] = *i*. Now let's take it to the next level:

Now if we remove the restriction 0 ≤ θ ≤ 2π, then we get the general solution

where *n* ∈ **Z**. I'm not sure why you have just *n* and not 2*n*, Ricky. Odd values of *n* in your solution would give

Now take a simple case of some 0 ≤ θ ≤ 2π that could give *e[sup]i*θ[/sup] = -i. 3π/2 is our value. Then

So, given the same interval 0 ≤ θ ≤ 2π, (-*i)[sup]i[/sup] ≠ i[sup]i[/sup]*, so I will conclude that your *n* should be 2*n*.

*Last edited by Zhylliolom (2006-07-13 10:07:19)*

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**Ricky****Moderator**- Registered: 2005-12-04
- Posts: 3,791

sin(3pi/2) doesn't equal 1, does it...

"In the real world, this would be a problem. But in mathematics, we can just define a place where this problem doesn't exist. So we'll go ahead and do that now..."

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**George,Y****Member**- Registered: 2006-03-12
- Posts: 1,306

Hey you guys are discussing something too difficult here!

Though I read it too.

Mathsisfun is good at fun maths and perhaps he is the best person you can consult to.

**X'(y-Xβ)=0**

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**RauLiTo****Member**- Registered: 2006-01-11
- Posts: 142

thank you alot guys

mr.mathisfun ... i think u have got alot of these topics ... i really like them

can i see more ?

ImPo$$!BLe = NoTH!nG

Go DowN DeeP iNTo aNyTHinG U WiLL FinD MaTHeMaTiCs ...

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**Devantè****Real Member**- Registered: 2006-07-14
- Posts: 6,400

Or you could just try looking in the Exercises forum. We're adding some every now and then, so check back regularly!

*Last edited by Devantè (2009-02-14 11:18:30)*

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