Mathematics

can someone help me solve these two equations (and please explain)? log9 (q) = log12 (p) = log18 (q + p) what is q and what is p? and.... sinA + sinB = (square root 2) over 2 cosA + cosB = (square root 6) over 2 sin(A + B) = ? Thanks in advanced!

which outcome has a greater occurence: having 4 rolls to land a six with one die, or having 36 rolls to land (2) 6's with 2 die?

I can't figure out how to do this algerbically, though I know the answer: There are 2 numbers that their sum is 100; and the product of the number is 24 times 100. The answers are 40 and 60. I have 2 equations: [math]x + y = 100[/math] and [math]xy=2400[/math], but I'm not exactly sure how to put it together and get the answers. Can anybody help me?

Can someone give me an example of Moore's Law used in real life? Thanks

I am wondering if anyone could factor this for me? [math]a^{4} + 2b^{4} + c^{4} - 2a^{2}c^{2} - 2a^{2}b^{2} + 2b^{2}c^{2}[/math]

Hi, I'm suggesting a new reinforcement learning algorithm applied in my case on robots, please see: http://www.compactech.com/kartoun/articles/html/Kartoun_RA_2005_September_3_2005_Accepted.htm'>http://www.compactech.com/kartoun/articles/html/Kartoun_RA_2005_September_3_2005_Accepted.htm I would like to describe the algorithm more scientifically; define it mathematically much better than described in the paper. I'm asking for guidance of how to prove an algorithm, for example in the form of convergence or superiority. How can I demonstrate advantages or disadvantages of an algorithm mathematically? How can I prove convergence or divergence? How …

I've just saw an article online about finding a recursive expression for pi through a formula of centripetal force. It doesn't tell you how though! Anyone's ever heard of this?

http://www.newscientist.com/article.ns?id=dn6151 Has he gone over the hill? Or do you still have faith in him still?

Your town has decided to drill a well to increase its water supply. As the town engineer, you have determined that a water tower will be necessary to provide the pressure needed for distribution, and you have designed the system shown below. The water is to be pumped from a 300-ft well through a vertical 4-in. pipe into the base of a cylindrical tank 20ft in diameter and 25 ft high. The base of the tank will be 60 ft above ground. The pump is a 3-hp pump, rated at 1650 ft*lb/sec. How long will it take to fill the tank the first time? (Include the time it takes to fill the pipe) (62.5 lb = 1 ft^3) I tried to do them separtely then add the work to fill the pip and tank …

Can someone help me with this problem? A 8.48 g sample of an unknown organic compound containing only carbon, hydrogen, and oxygen was burned completely to produce 12.42 g of carbon dioxide and 5.08 g of water. Find the percentage of carbon, hydrogen, and oxygen in the compound. I just need to know how to get started, and what to do, my teacher confused herself on this one and no one in the class can do it.

If kx^2 - kx - 6 is divisible by both (x + 1) and (x + m), find the value of m. Given 2/x = y/3 = x/y , find x^3. One way to pack a 100 by 100 square with 10,000 circles, each of diameter 1, is to put them in 100 rows with 100 circles in each row. If the circles are repacked so that the centers of any three tangent circles form an equilateral triangle, what is the maximum number of additional circles that can be packed?

The integers 1,2,3,...,100 are written on the board. What is the smallest number of these integers that can be wiped off so that the product of the remaining integers ends in 2?

How would one measure the length of a spiral? I tried figuring it out with nothing but a piece of paper and a pencil, but could figure nothing. I have a feeling it might have something to do with log, cos, sin, and/or tan. Thank's in advance for your help, and I'm sorry if I sound stupid.

I can't remember how to solve this, any help would be appreciated, thank you.

Can anybody explain to me what is the difference between parameter and arbitrary?

I wrote a script that is designed to aid the process of trying to memorise 100 digits of pi. I played with it for an hour last night and this morning I still remember them, I will play it every now and again until the numbers are off by heart. Here is the page you can test it out on: http://www.random.abrahamjoffe.com.au/public/JavaScripts/pi.htm Let me know what you think and if you can imagine perhaps a more effective method I might try. 3. 14159 26535 89793 23846 26433 83279 50288 41971 69399 37510 58209 74944 59230 78164 06286 20899 86280 34825 34211 70679

Go to this thread http://antipsykopat.org/miniBB/index.php? action=vthread&forum=9&topic=12012 and proof that 0.9999....=1 You can of course write in English even though most of it is already written in another language, but everyone there understands English. Why have the Norwegian philosopher Alpha offered this kind of money? It is needed to proof that it can't be 1, because the universe is virtual reality and humans have non-physical soul. It has been showed that the world is not mehanical in amongst other things the Aspect-experiment, and there is something that lies beneath it all, like a computer that controls what is going on on a monito…

I don't know how to isolate an exponent with a variable and a known number, e.g. [math]2 = 3^{0.01t}[/math]. How do I isolate the term 't'? I know that you can square root the opposite side to remove the exponential, like this: [math]\sqrt[0.01t]{2}=3[/math]. But that still doesn't solve the isolation of the term 't'. Any help??

I have a problem with the following: a and b are non-parallel vectors. Choose two numbers x and y so that 3r_1 = 2r_2 can be applied to the following vectors r_1 := (x + 4y) a + (2x + y + 1) b r_2 := (y - 2x + 2) a + (2x - 3y - 1)b Now, I have no idea what to do with the vectors. I could solve it if it were just for x and y without a, b and r, but I don't know whether to just drop the vectors, use some vectors i choose myself or if I have to calculate it with a and b left there as a variable. The solution is x = 2 and y = -1 btw, but even with that information I can't deduce the proper way of calculating it. Can someone give me a hint as to ho…

Is there any type of equation that would represent the total possible amount of sudoku games there are possible to make?

Hi everyone! Here's the ongoing challenge: Using any mathematical operations you want, but only four 4s (Or less) for the numbers, create equations to equal as many numbers as possible. Here are the rules: 1. All four "4"s must be used in each equation. 2. No other numbers can be used in the equations. 3. You may use any mathematical operations and symbols (not including symbols for other numbers, like Pi, e, etc.) you wish. 4. The answers in this thread will start with trying to find an answer resulting in 1, then the next person must find a solution resulting in 2, the next person 3, and so on. 5. This is to continue as long as answers can be found. 6. …

As the following: Find the maximum value of: (a^2/sinb)*[cos(b-2n)-cosb] express in terms of a and b; where n is varied (find a formula in a and b that is the greatest) In fact, this question is derived from a figure, the topic is compound angles, and I would like to know if there is any way to get the answer more faster and make less error, if yes, how to do so.

What are we all reading, maths-wise? Mention your second year complex analysis textbook if you really want to, but I'm interested in hearing about what people (especially postgrads, postdocs, whatever category Matt Grime falls into, and PeopleWhoOnceWereMathmosButThenTurnedTraitor - like me) are reading about maths in their spare time. I'll start off with my current - Modular Forms and Fermat's Last Theorem. It's not easy by any stretch, but it's interesting. What about you?

Here is an extradiotary cool math trick. Try it yourself! 1. Grab a calculator (You won't be able to do this one in your head) 2. Key in the first three digits of your phone number (NOT the area code) 3. Multiply by 80 4. Add 1 5. Multiply by 250 6. Add the last 4 digits of your phone number 7. Add the last 4 digits of your phone number again 8. Subtract 250 9. Divide number by 2 Do you recognize the answer? It's like magic, eh?

Hey all SFNers... Um just to let you know that in support of giving InternationalDiscussionForums.net some special content, I have been posting there exclusively some of the interesting math problems what I would be posting here. I mean, IDF is a pretty cool place, and its run by some of your fellow SFNers, so you'll probably feel comfortable there, and I've been posting interesting math problems there. This isn't meant to be an advertisement, just an announcement of where I've put some math problems that people who enjoy this forum would probably enjoy. But I mean, don't go if you don't want to, because this isn't an advertisement.