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#26 Re: Help Me ! » need help in simple computation for my thory » 2014-10-26 06:03:14

martnSpruce wrote:

I said that you need all primes X/2 to sieve X. Isnt this obivious?

Don't you only need the primes that are less than sqrtX to sieve X?

@martnSpruce I think your idea is interesting but I find it slightly hard to distinguish it from the Sieve of Eratosthenes.

#27 Re: Help Me ! » stuff in a box » 2014-10-26 05:51:39

Would the answer be 25\sqrt{29} all over 6?

#28 Re: Help Me ! » some 3d stuff :D » 2014-10-26 05:46:39

So x is $\frac{2-\sqrt{2}}{2}$

#29 Re: Help Me ! » stuff in a box » 2014-10-25 12:28:50

What is the perpendicular height in this case?
Don't expect a reply for another 24 hrs... Thanks in advance

Solar Devil

#30 Re: Help Me ! » some 3d stuff :D » 2014-10-25 12:20:22

I don't get how you get x. Could you help?

#31 Re: Help Me ! » How to name a plane » 2014-09-21 05:53:15

The plane in geometry is mainly defined with 3 points on the plane.

Solar

#32 Re: Help Me ! » Geo Problems » 2014-09-21 05:49:52

Hello

I was looking at these set of posts but still don't get how to get number 3. Could you help?

Thanks
SolarDevil

#34 Re: Help Me ! » Geometry Polygon Angles » 2014-09-15 10:17:40

Thank you so much! So the answer would be 78? If not, what are my errors.
Once again, thank you so much!

#35 Re: Help Me ! » Geometry Polygon Angles » 2014-09-15 00:30:36

Sorry for the late reply. Points C and D are on the heptagon and the 15-gon respectively where C and D are adjacent to point A.

Thanks
SolarDevil

#36 Help Me ! » Geometry Polygon Angles » 2014-09-14 12:52:18

SolarDevil
Replies: 8

Hey! I have had some trouble figuring out this problem and would like some help, please show me your solution!

A regular heptagon and a regular 15-gon share a common edge AB, as shown. Find angle BCD, in degrees.

Sorry I didn't supply a drawing.

Thanks
SolarDevil

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