Science & Mathematics - 19 September 2007

Please help me find dy/dx of the
arctan (y/x) = 1/2 * ln(x^2+y^2)
I don't know what kind of this function is to find the derivative. Is it implicit function?

2007-09-19 20:36:25 · 3 answers · asked by Phuong Nam 2 in Mathematics

2007-09-19 20:29:59 · 7 answers · asked by srikantkumarrath r 1 in Mathematics

2007-09-19 20:28:07 · 1 answers · asked by Anonymous in Earth Sciences & Geology

2007-09-19 20:20:48 · 2 answers · asked by Anonymous in Chemistry

2007-09-19 20:14:23 · 2 answers · asked by - 3 in Astronomy & Space

I don't mean the little RFID chips that everything is getting implanted with. I mean real implants. Small bluetooth speakers in the back of your ears? A MP3 player in the hip? Is any of it posible? Would any one do it if it was?

2007-09-19 20:10:53 · 5 answers · asked by willlee00 1 in Other - Alternative

2007-09-19 20:10:42 · 6 answers · asked by Anonymous in Mathematics

The lowest common multiple of 6, 15 and x is 150. Write down the least value of x.

The working solutions:

1) First do the LCM working...Thus the LCM is 2,3,5 and 1.

Then 6 = 2 * 3
15 = 5*3

Least value of x = 5^2 =25

I don't understand about the last part...Why they have to use 5^2 to get 25? In the LCM working, there is only 1 five...So, how and why they mulitply the 5 twice to get 25? I don't understand....Please help..You could also explain the question in your own method

2007-09-19 20:09:20 · 3 answers · asked by Anonymous in Mathematics

All I need is the equation for the following problem:
Bart's age is one third of his mother's age. Seven years ago, his age was one fifth hers. How old are both now?


Can someone tell me the equation for this problem?

2007-09-19 20:07:37 · 2 answers · asked by xhollywoodthrash 1 in Mathematics

2007-09-19 19:54:13 · 7 answers · asked by aryan e 1 in Physics

I've been writting a story for a little while now, and as it's a sci-fi story, there is some space traveling. I have a very specific place in mind, but I want to be sure this place is at least plausible to exist in real life.

The specifications are:
It must be within 12 light years from our Sun.
Should be made mostly of water. (>=90%)
Needs to be in a non-lethal star system. (Not too much radiation, please!)

The other questions I'd like answered would be what would the maximum size of such a planet be, and under what circumstances, besides those I already mentioned, would life likely occur?

Beyond that, I believe I have what I need. Thanks for any help.

2007-09-19 19:49:42 · 6 answers · asked by Anonymous in Astronomy & Space

Describe all the forces acting on a child riding a horse on a merry-go-round. Which of these forces provides the centripetal acceleration of the child?

2007-09-19 19:47:22 · 3 answers · asked by Doc^chem 2 in Physics

2007-09-19 19:38:05 · 2 answers · asked by jayaprakash s 1 in Engineering

Where can I find it? What is the generic drug name of steerometh?

2007-09-19 19:35:38 · 1 answers · asked by jojie 1 in Medicine

2007-09-19 19:34:39 · 1 answers · asked by Help_me 1 in Chemistry

1. In the game of tic-tac-toe, what is the greatest number of squares that may be left unmarked when a game is won?

2. The number of rings in the olympic flag is a prime number that is a factor of 105, 20, and 30. How many rings are there?

3. The span of the Golden Gate Bridge in San Francisco is 1080 feet less than a mile. How long is the bridge?

4. The number of days that Mercury takes to evolve around the sun is a palindromic number, each digit is a cube greater than 1, how many days is one revolution around the sun?

2007-09-19 19:32:28 · 4 answers · asked by julia 1 in Mathematics

2007-09-19 19:31:07 · 2 answers · asked by anands k 1 in Physics

2007-09-19 19:30:18 · 4 answers · asked by alejandra a 1 in Medicine

A projectile is launched with an initial speed of 75m/s at an angle of 40' above the horizon. The projectile lands on a hillside 5.0s later. Neglect air friction. a) What is the projectile's velocity at it's highest point of its trajectory? b) What is the straight-line distance from where the projectile was launched to where it hits its target? (Note that the hill may slope up or down from the launch point.)

I was able to calculate a) as 57.45 m/s, but I am unable to figure out b. Can anyone help me?

2007-09-19 19:27:19 · 4 answers · asked by lostinphysics 2 in Physics

2007-09-19 19:23:22 · 3 answers · asked by Help_me 1 in Chemistry

2007-09-19 19:21:48 · 6 answers · asked by Anonymous in Zoology

for calculating land, pls. tell me how to change 2 beegha 17 biswa into acre

2007-09-19 19:18:29 · 2 answers · asked by tea2 1 in Mathematics

it seems as though every shred of evidence of it was taken off the net :P http://www.southparkstuff.com/season_6/episode_612/epi612script/
southpark at least alludes to it ;)
http://www.southparkstudios.com/downloads/display_image.php?ep_number=612&ep_name=A%20Ladder%20to%20Heaven&img=http://images.southparkstudios.com/media/images/612/ep612_image_04.jpg&img_name=The%20fake%20Japanese%20Heaven%20set
"Sharon: Randy! Gerald! We, we were wrong about heaven! The Japanese just reached it with their ladder!"
"Correspondent: This is a Nobunaga Hiroichi reporting rive from hayben. [behind him is a set with clouds hanging from wires. Angels swing into place slowly] The great a-nation of Japan reached a-hayben today about eight o'crock Pacific Standard Time-eh. [one of the angels falls off her rope and hits the ground. The correspondent sees this and moves in front of her to block the shot. Someone enters the shot and plants a Japanese flag among the clouds] ...."

2007-09-19 19:12:06 · 2 answers · asked by bandaidsrcool 2 in Astronomy & Space

Ok I understand how to simplify in class with these easy examples we get but I get hom and I get

x^2 x^6
______
x^3

Now when we get these x's I get confused. Any help and explanation is appreciated. Also if you know any good sites that would be helpfull. Thanks

2007-09-19 18:50:16 · 8 answers · asked by BrandyJo 3 in Mathematics

2007-09-19 18:44:10 · 5 answers · asked by shanabanana922 2 in Biology

I am looking for a women mathematician who was also a scientist and translator. She was born in France during the Enlightenment and was the daughter of an aristocratic family.
Please help!

2007-09-19 18:36:53 · 2 answers · asked by Anonymous in Mathematics

but I'm looking for the darkest area I can find for miles.

do you have any suggestions?
I'm planning on making a trip out of it and go camping for a few nights.

I'd like to be able to find it easily on google earth

2007-09-19 18:36:29 · 8 answers · asked by Mercury 2010 7 in Astronomy & Space

cos π/5 + cos 3π/5 = 1/2

This one is very troubling...

^_^

2007-09-19 18:35:17 · 4 answers · asked by kevin! 5 in Mathematics

2007-09-19 18:30:57 · 37 answers · asked by Life goes on... 6 in Paranormal Phenomena

solve for the angle theta in the following equation

2007-09-19 18:30:07 · 3 answers · asked by Anonymous in Mathematics