Science & Mathematics - 14 August 2007

y = (2x+3)^3 / root4x-7

the root4x-7 = (4x-7)^1/2 i just didnt know how to write it haha

i know you use quotiant rule and chain rule. I get up to this:
= [3(2x+3)^2 (4x-7)^1/2 - 1/2(4x-7)^-1/2 (2x+3)^3 / 4x-7 ] 8
am i on the right track ?
haha thanks =)

2007-08-14 18:50:41 · 3 answers · asked by Henry Chan 1 in Mathematics

Why is seperating salt from salt water difficult? What theories are out there for new ways to do it? What about evaporation, but then how will we take the gaseous H2O back to liquid state?

2007-08-14 18:46:24 · 8 answers · asked by Omar C 1 in Earth Sciences & Geology

2007-08-14 18:43:46 · 10 answers · asked by m m 1 in Physics

tomarrow im going to a concert so i checked the weather, and, its supposed to be 83 degrees, with morning rainshowers. the doors open at 11:45. so, first question-- do you think it will rain during the concert? next-- what should i wear, due to the weather?
thanks

2007-08-14 18:40:12 · 3 answers · asked by Anonymous in Weather

Maxine & Sammy have the same amount of lawn.

maxine can mow the lawn in 24 min.
sammy can mow the lawn in 36 min.

At what time will sammy have twice as much lawn to mow as maxine?

2007-08-14 18:36:48 · 6 answers · asked by thee.mighty.m 1 in Mathematics

For i = , if 3i (2 + 5i) = x + 6i, then x = ?
A. –15
B. 5
C. 5i
D. 15i
E. 27i

the answer is a

2007-08-14 18:36:05 · 6 answers · asked by Anonymous in Mathematics

Barry can do a certain job in 5 hrs. Whereas If mike helps him, it takes them 4 hrs to do the job working together. How long would it take mike to complete the job by him self?

Please explain the concept behind this problem? What is a good way to approach problems like this?

2007-08-14 18:30:31 · 4 answers · asked by Anonymous in Mathematics

everytime i go to the doctor and get shots(vaccines or vitamin B shots for example) in my arm, it hurts a lot.why isn't the needle injected in our vein like an IV, so it's less painless and the medicine is effective quicker?

doctors/nurse:please explain.

2007-08-14 18:26:21 · 5 answers · asked by polly-pocket 5 in Medicine

What are some examples of flywheel devices being used in toys and other machines? And what is it that makes a flywheel so special?

2007-08-14 18:23:55 · 5 answers · asked by spacebendingguy 1 in Engineering

17. A 60W incandescent light bulb is 5% efficient. A 60W fluorescent bulb is 15% efficient. How much more light will the florescent light bulb give off than the incandescent light bulb, in the same period of time?

2007-08-14 18:21:42 · 2 answers · asked by Anonymous in Physics

I broke my glass("tabacco") pipe into 2, the breal is clean and smooth would it be possible to melt each peace and put them together??
Or, Is there a glue that can with stand heat with out detatching

2007-08-14 18:14:51 · 4 answers · asked by Tk 1 in Engineering

The number of bacteria in a culture is given by the formula:
N=N[low 0] e^kt
where t is time in hours.

In a certain culture, the bacteria increased from 2000 to 7000 in 6 hours. What is the percentage rate of increase?

2007-08-14 18:12:11 · 2 answers · asked by th3one101 2 in Mathematics

Turbine rating 500 MW, 3000rpm and TG is connected to the grid. Turbine inlet steam pressure is 160 kg/cm2 and 550deg C.

2007-08-14 18:05:16 · 4 answers · asked by SUJAY 1 in Engineering

THANK YOU SO MUCH.

2007-08-14 17:56:37 · 4 answers · asked by sweetcalm<3 3 in Mathematics

2007-08-14 17:56:27 · 4 answers · asked by SUJAY 1 in Engineering

Okay so I'm doing my homework and this seemed to confuse me. So I live in Arizona, it's super hot and no rain. And it said in my homework, "The higher a location's temperature, the more easily water evaporates at that location." and that makes sense, but so does that mean the slower the evaporation, the more precipitation? I'm confused...

2007-08-14 17:54:06 · 2 answers · asked by Anonymous in Earth Sciences & Geology

If in fact a storm of this nature may have the chance to potentially produce full ocean storms as the overall planet temperatures rise?

2007-08-14 17:43:52 · 3 answers · asked by stratoframe 5 in Weather

solve the equation... show work please!!
thanks

x+1 -2sqrt(x+11)=0

2007-08-14 17:42:46 · 4 answers · asked by sexycheerleader2009 3 in Mathematics

How much vacation time do physicians get? I think someone I know gets 5 or 6 weeks.

2007-08-14 17:39:30 · 9 answers · asked by DF25 1 in Medicine

Alright, OD has come up a lot in the world, recently. At least it seems that way to me. So im doing research. (I do this randomly with things im not familiar with) And as much as i research, it doesnt say what pills kill people. Like i know, ODing on something for say acne, wouldnt kill you right? Im just wondering. Also, someone in my family once OD'ed but didnt die. And i was wondering like what type of perscription they took. IDK....im just curious on the subject. If anyone has any knowledge on the subject, please let me know!

2007-08-14 17:35:10 · 17 answers · asked by Anonymous in Medicine

I need to know the start and end time zone of different country that are affected by the DLS.

URGENTLY!!! PLEASE!!

2007-08-14 17:32:52 · 1 answers · asked by what hack? 2 in Geography

Im talking about..shielding the craft from the Earths gravitational field..and please,, dont tell me it cant be done...this question is strictly for those with an imagination..and those who try to think outside the box.

2007-08-14 17:28:40 · 4 answers · asked by Joseph 2 in Physics

on 8y+20=y+2y-5y (i got y=20) on 4b-10=b+3b-2b(i got b=5) on -7f+2f=-36+f+3f(i got f=-9) on -5a+7a=-18+3a+5a(i got a=-3) on 9y+2=3(y+4) (i got 14/6 but stuck)

2007-08-14 17:28:22 · 3 answers · asked by dularu s 1 in Mathematics

a) compute dy/dx
I got (16x-5y)/(5x + y^2)

b)write an equation for the line tangent to the curve at the point (4,-1)
I plugged the numbers in the derivative and then got (y+1)=3(x - 4)

c)there is a number k so that the point (4.2,k) is on the curve. Using the tangent line found in part b, approximate value of k ..
so I dont know if this is right but I just plugged those numbers..
k+1=3(4.2 - 4) and got k= -0.4

d)write an equation that can be solved to find k so that the point (4.2, k) is on the curve..
What do I do for this one?

e) Solve the equation found in d for the value of k.

Can someone help me?
Thanks!

2007-08-14 17:27:13 · 2 answers · asked by Anonymous in Mathematics

Ok so here in west TN we are having yet another water shortage. And for the life of me I don't get why its always in the same spot which is like 1 mile to 2 miles from Kentucky lake. Does anyone have any idea they could offer me?

2007-08-14 17:21:40 · 3 answers · asked by Anonymous in Earth Sciences & Geology

2007-08-14 17:15:58 · 3 answers · asked by Shashank B 1 in Physics

2007-08-14 17:15:38 · 5 answers · asked by joseph j 1 in Physics

on 4-9ju=j+4 (I got j=1 )on 6n-4n+20 (i got n=2)on 11e=9e+14 (i got e=7) on 5d-4=2d+6(i got it wrong) on 2j-5=8j+7(i got wrong also) these are hard for me to explain to my son.

2007-08-14 17:15:33 · 10 answers · asked by dularu s 1 in Mathematics

2007-08-14 17:14:53 · 1 answers · asked by Shashank B 1 in Physics

2007-08-14 17:09:08 · 8 answers · asked by tonya t 1 in Mathematics