Science & Mathematics - 24 October 2006

2(sin x)^2 - 5 cos x - 4 = 0

x=________ pi


Note: the answer must be an integer or a fraction.

I want to know if your answer is the same as mine. Thanks in advance.

2006-10-24 19:41:50 · 4 answers · asked by pnoiz1 2 in Mathematics

2006-10-24 19:40:53 · 4 answers · asked by TIRTHA_CHAK 1 in Engineering

(Low-Density Polyethylene Plastics) LDPEs to be specific..

2006-10-24 19:37:28 · 3 answers · asked by avon_manu1009 2 in Chemistry

Is there any trick for finding the determinant of this 4x4 matrix?

[ 1, 1, 1, 1 ]
[ 1+a, 1, 1, 1 ]
[ 1, 1+b,1, 1 ]
[ 1, 1, 1+c, 1 ]

2006-10-24 19:35:05 · 6 answers · asked by Amir E 1 in Mathematics

Solve by completing the square...

2x^2 - 7x + 1 = 0

show your work

2006-10-24 19:34:14 · 8 answers · asked by Anonymous in Mathematics

Find the exact solution(s) to this problem...

lx+5l is greater than 2

Meaning, the absolute value of (x+5) is greater than 2

show your work

2006-10-24 19:32:20 · 5 answers · asked by Anonymous in Mathematics

Find the exact solution(s) to this equation

(3)/(3x+4) + (2)/(x-1) = 2


and show your work

2006-10-24 19:30:23 · 8 answers · asked by Anonymous in Mathematics

I've figured out how many moles I am dealing with, now I need to determine the total pressure of the container when there are 1.025 mol and the volume of the container is 5.00 L and the temperature is 19degrees celsius (which I will need to convert to Kelvin). Being I am looking for pressure, would I be solving for p? Oh and how do I convert celsius to kelvin again?

2006-10-24 19:29:33 · 3 answers · asked by D 2 in Chemistry

2006-10-24 19:23:55 · 1 answers · asked by cheezzznitz 5 in Chemistry

2006-10-24 19:21:44 · 1 answers · asked by cheezzznitz 5 in Chemistry

3 points question
Physics o-lvel

2006-10-24 19:20:24 · 10 answers · asked by Anonymous in Physics

2006-10-24 19:20:01 · 5 answers · asked by simi das 1 in Biology

Like find the ionic concentrations of, let's say, Na2 or CO3

2006-10-24 19:18:13 · 1 answers · asked by cheezzznitz 5 in Chemistry

Of the reaction HCL + Na2CO3 --> ????
It is equimolar.

Please list ionic products from the least to greatest concentration?

2006-10-24 19:17:08 · 1 answers · asked by cheezzznitz 5 in Chemistry

Guesses: Urdu, Bengali, Welsh, Cantonese ?

2006-10-24 19:14:29 · 12 answers · asked by Perseus 3 in Other - Science

Ti3+ + HOBr <===> TiO2+ + Br¯ (in acid solution)

(a) Write the correctly balanced half-reaction and net ionic equation for the skeletal equation shown above.

Ti3+ + H2O ---> TiO2+ + 2 H+ + e¯

H+ + HOBr + 2e¯ ---> Br¯ + H2O

2 Ti3+ + HOBr + H2O ---> 2 TiO2+ + 3 H+ + Br¯

(b) Identify the oxidizing agent and the reducing agent in this reaction.

HOBr is the oxidizing agent and Ti3+ is the reducing agent.
--------------------------------
My question: The resulting Br- precipitates with silver nitrate. The final precipitate is 2.504 grams. What is the initial concentration of HOBr if initial solution is .5 liters?

2006-10-24 19:13:15 · 1 answers · asked by cheezzznitz 5 in Chemistry

i couldnt solve this. just curious if anyone else could... :)


f(x) = x^2 (sin(1/x)) when x does not = 0
0 when x=0

a) using the definition of the derivative, prove that f is differentiable at x=0

b)show that f ' (x) is not continuous at x =0.

2006-10-24 19:10:17 · 4 answers · asked by leksa27 2 in Mathematics

2006-10-24 19:09:26 · 4 answers · asked by VeNom 1 in Chemistry

Trying to fail/pass a urine test.

2006-10-24 19:07:05 · 6 answers · asked by No One 1 in Biology

2006-10-24 19:06:57 · 1 answers · asked by cheezzznitz 5 in Chemistry

I was able to determine for oxygen, as it's only 1, but carbon dioxide is two elements. I am needing to convert 1.1 grams of carbon dioxide to moles. Part of my problem was converting 16.0 grams of oxygen to moles, which was determined to be 1 (I hope).

2006-10-24 19:06:09 · 4 answers · asked by D 2 in Chemistry

How many g of Na3PO4 is produced by 75.7g of H3PO4?

2006-10-24 19:05:06 · 4 answers · asked by noodlenmac0329 2 in Chemistry

Let p and q be real numbers and let f be the function defined by:

f(x) = 1+2p(x-1)+(x-1)^2 for x
= qx + p for x>1

a) find the value of q, in terms of p, for which f is continuous at x=1
b) find the values of p and q for which f is differentiable at x=1

thanks for the help!

2006-10-24 19:00:39 · 1 answers · asked by leksa27 2 in Mathematics

I am going to create a message board (forum) that is for homework help (mostly high school homework). The forum is only gong to concentrate on giving help in science and math subjects. What could be a good name for the fourm? I need help comming up with a name for the forum.

2006-10-24 18:57:31 · 6 answers · asked by aftababhan 2 in Mathematics

let f be the function that is given by f(x) = (ax+b) / (x^2 - c) and has the following properties:
1) the graph of f is symmetric to the y axis
2)lim as x approaches 2 from the right = + infinity
3)f ' (1)= -2

What are the values of a, b, and c?
What are the vertical and horizontal asymptotes?


thank you sosososososososososo much

2006-10-24 18:57:27 · 3 answers · asked by leksa27 2 in Mathematics

to the nearest millionth.

2006-10-24 18:52:15 · 29 answers · asked by Anonymous in Mathematics

A 3.00 g sample of an alloy (containing only Pb and Sn) was dissolved in nitric acid (HNO3). Sulfuric acid was added to this solution, which precipitated 2.93 g of PbSO4. Assuming that all of the lead was precipitated, what is the precentage of Sn in the sample?

2006-10-24 18:44:02 · 5 answers · asked by kruzzz80 2 in Chemistry

x^3 - 3x^2 +2

2006-10-24 18:43:36 · 5 answers · asked by leksa27 2 in Mathematics

for a school project, i need to boil cold water using a vacuum pump. I did some research, but i still didn't find what i needed. I need to know what kind of pump i need for this, and where i can get one for cheap, since i will only use it for this project. if you know how to actually use it, you can throw that in as well. thanks!

2006-10-24 18:42:20 · 8 answers · asked by HoldYourColor 3 in Physics

I need help I'm not sure how to solve this inequality..

I r - 8 I = 2

2006-10-24 18:38:49 · 7 answers · asked by Anonymous in Mathematics