## Search found 206 matches

Tue Nov 17, 2009 12:15 am UTC
Forum: Mathematics
Topic: Quick Probability Question
Replies: 5
Views: 902

### Re: Quick Probability Question

If you guess "Prime" or "not Prime" with a 50-50 chance, then whichever one is right, you have a 50% chance of choosing that one. So, yes, you did it right.
With a 50% chance, 7 out of 12 isn't very significant. 8/12, maybe, but not 7/12.
Fri Nov 06, 2009 1:08 am UTC
Forum: Gaming
Topic: Favorite game of all time?
Replies: 79
Views: 8463

### Re: Favorite game of all time?

La-Mulana- for its music, atmosphere, difficulty, and most of all charm.
A close second would be Touhou: Imperishable Night, for most of the same reasons.
Fri Oct 30, 2009 6:05 pm UTC
Forum: Mathematics
Topic: Apparently easy complex number problem
Replies: 20
Views: 2100

### Re: Apparently easy complex number problem

Think about it geometrically. If z/(z-i) is real, z and z-i have the same angle from the origin (because division of complex numbers subtracts the angles.) So, 0, z, and z-i are all in a straight line. But z-i is directly vertical from z, so z must be directly vertical from 0. Theref...
Wed Oct 28, 2009 9:22 pm UTC
Forum: Coding
Topic: Project Euler
Replies: 411
Views: 157093

### Re: Project Euler

Oh, silly me. It works now, thanks!
Tue Oct 27, 2009 11:54 pm UTC
Forum: Coding
Topic: Project Euler
Replies: 411
Views: 157093

### Re: Project Euler

I'm doing #14: n -> n/2 if n is even n -> 3n+1 if n is odd Which number under 1,000,000 takes the longest to get to 1? My algorithm is a sort of "branching out" thing. I start with 1, and in each step: 1) If n was just added to the list, add 2n to the list. 2) If n was just added to the li...
Tue Oct 27, 2009 11:36 pm UTC
Forum: Mathematics
Topic: optimization - help needed
Replies: 8
Views: 1010

### Re: optimization - help needed

Oblivion wrote:SA=2x^2+4xy+2x+4y = 162.24

Oblivion wrote:solving for y, 2x^2+2x-162.24=4xy+4y

Oblivion wrote:(2x^2+2x-162.24)/4y=x

Maybe I'm just being silly, but I think you made an error here.

EDIT: Also, a hint: don't try to get x=(something), try to get y=(something). It works out much nicer.