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phantasm
04-28-2009, 03:53 PM
I'm using math for its main purpose in life...video games....but I can't seem to figure out how to solve this equation for S so I can easily graph some values. I need your help.


100 * log(( 3*S + 2*I + C) / 30 ) / log(2*M) = 100

Khariz
04-28-2009, 03:54 PM
Yollia, you can handle this one.

Sean of the Thread
04-28-2009, 04:00 PM
Bobmuthol is good at that shit hit him up for a solution.

BriarFox
04-28-2009, 04:01 PM
I'm using math for its main purpose in life...video games....but I can't seem to figure out how to solve this equation for S so I can easily graph some values. I need your help.


100 * log(( 3*S + 2*I + C) / 30 ) / log(2*M) = 100

Huh. What's it for? It's odd that the whole log...M sequence is just going to equal 1 no matter what.

Edit: Oh, unless that 100 only applies to the top half of the equation?

Xaerve
04-28-2009, 04:05 PM
assuming I is infinity:
S = -(2)(NTIF)/3 +/- 2M/3

assuming I is a variable:
S = [-(2x)/3] - [c/3] +/- 20M

Trouble
04-28-2009, 04:06 PM
OK I haven't done math in 15 years but this is what I came up with:

s = 5/m - 2i/3 -c/3

phantasm
04-28-2009, 04:06 PM
Its a formula that yields a %chance to cast.

S = Spell Rank
I = Int stat
C = Spell Craft skill ranks
M = Manacost of spell

I want to solve for different training plans that will still give 100% chance to cast so I set the equation equal to 100.


[100 * log(( 3*S + 2*I + C) / 30 ) / log(2*M) ] = 100

I'll manually switch the M and C variables, but I need to have it in Y=X form so I can easilly graph them in WZGrapher.

ElvenFury
04-28-2009, 04:16 PM
My math is also rusty. So I ended up with S = (60m - C - 2i)/3

I'm assuming that I'm wrong though.

phantasm
04-28-2009, 04:20 PM
Okay, I'll test these out and see if any of them give the same results as the original. I'm also curious what identities you use to get the variables out of the logarithm.

Xaerve
04-28-2009, 04:21 PM
Mine answers be right.

phantasm
04-28-2009, 04:26 PM
assuming I is infinity:
S = -(2)(NTIF)/3 +/- 2M/3

assuming I is a variable:
S = [-(2x)/3] - [c/3] +/- 20M


Woot, Xaerves's equation is giving proper results. Thanks. Assuming I is a variable and you mistyped it as x.

ElvenFury
04-28-2009, 04:27 PM
Mine answers be right.

Where did you get X from?

Xaerve
04-28-2009, 04:27 PM
Replaced the variable I with the variable X; I, when dealing with Logs, usually refers to Infinity.

Also, please post copious logs of your results!

phantasm
04-28-2009, 04:29 PM
Are you going to post how you solved it. I'd really like to know.

ElvenFury
04-28-2009, 04:29 PM
Replaced the variable I with the variable X; I, when dealing with Logs, usually refers to Infinity.

Also, please post copious logs of your results!

Ok, gotcha. Then our answers are pretty much the same thing, you just simplified M a bit, right?

(I was also confused by i at first)

Xaerve
04-28-2009, 04:33 PM
I could scan my paper I guess, I'm not typing all that out!

EF: Yes, simplified M.

Sean of the Thread
04-28-2009, 04:34 PM
Will you take my online math courses next semester?

I'm sure we can work something out.

ElvenFury
04-28-2009, 04:42 PM
100 * log(( 3*S + 2*I + C) / 30 ) / log(2*M) = 100

Divide both sides by 100 to get:

log[(3s + 2i + C)/30] / log2m = 1

Multiply both sides by Log2m:

log[(3s + 2i + C)/30] = log2m

Get rid of the logs:

(3s + 2i + C)/30 = 2m

*30:

3s + 2i + C = 60m

Subtract the remaining junk and divide by 3 to get:

s = (60m -2i - C)/3

"Simplify" to:

s = 20m - (2i/3) - (c/3)

That's how I did it, anyway.

Xaerve
04-28-2009, 04:46 PM
Thanks for saving me the time :)

Nice work.

Sean of the Thread
04-28-2009, 04:48 PM
You fuckers make me sick to my stomach.

ElvenFury
04-28-2009, 04:48 PM
It's been so long that I had to look up logarithms because I forgot what the hell they did. Luckily they ended up canceling each other out anyway. LOL

Xaerve: Thanks, and you're welcome.

Phantasm: You're welcome.

Sean: Sorry.

:-)

phantasm
04-28-2009, 04:51 PM
Thats awesome thank you.

Euler
04-28-2009, 06:32 PM
nerds.

Bobmuhthol
04-28-2009, 06:36 PM
lol, thanks for believing in me, Sean. I wish I saw this thread sooner.