Mathematics - 10 September 2007

Is it:
a) the width of b-a
b) the width of a single sub-rectangle (one of those infinite tiny rectangles)

The resaon I ask is to get a better deeper understanding of the arithmatic involved in integrals. The question occured when doing substution...

∫sin(2x) dx

substitute:
u=2x
du/dx = 2
dx = 1/2 du

now I replace the "dx" in the original equation, yada yada.

So what exactly is dx? I don't want to just midlessly do arithmatic.

Just hoping for an 'aha!' moment here. :-)
Thanks

2007-09-10 23:26:13 · 4 answers · asked by RogerDodger 1

Show that the line with intercepts (a, 0) and (0, b) has the following equation:

x/a + y/b = 1, a can NOT = 0, b can NOT = 0.

Please explain how you got your answers.
Thanks.

2007-09-10 22:54:53 · 6 answers · asked by Matthew K 2

That makes total sense thx heaps. I tried to do the next one with same formula.

S=6, u=11, a=4
S=ut + 1/2 at (squared)

6=11t + (1/2) 4t (squared)
0=11t + 2t (squared) - 6
0=2t (squared) + 11t - 6
0=t (squared) + 11t - 12
0= (t-1)(t+12)
t=1, -12 therefore 1...

But answer is 1/2, -6?? Help again please?? Im trying..

2007-09-10 22:25:52 · 3 answers · asked by Anonymous

i want teaching math with games and puzzles in high school, for example i want teach limits with games , but i dont find good sites for using. who can help me?

2007-09-10 22:14:29 · 3 answers · asked by zahra 1

A class of 30 students had an average (arithmetic mean) of 92 points on a geography test out of possible 100. If 10 of the students had a perfect score, what was the average score for the remaining students?

a. 58
b. 87
c. 88
d. 90
e. 92

2007-09-10 22:01:12 · 5 answers · asked by king_24680 1

Find the radius of curvature and the center of curvature for f (t) = at t =pi/2

2007-09-10 21:55:55 · 3 answers · asked by Anonymous

2007-09-10 21:47:19 · 12 answers · asked by Anonymous

For the formula S= ut + 1/2 at squared, find the values of t if:
S=18, u=7, a=2

Please tell me step by step on how to find t please?? 10 points?

2007-09-10 21:39:25 · 9 answers · asked by Anonymous

1x2x3x4x5x6x7x8x9x10

2007-09-10 21:38:40 · 6 answers · asked by Anonymous

This starts out as:
f(x)=1/x
I need to find and simplify using the difference quotient:
f(x+h) - f(x)
---------------
h

I have gotten as far as:
1/x+h - 1/x
--------------
h

The final answer is:
- 1
--------
x(x+h)

But I need to figure out the step(s) to that point.

2007-09-10 20:17:24 · 6 answers · asked by Riel Billy 1

Kevin wants a certain amount of platforms that each have a constant increase in height between the shortest and the tallest platform. He needs to decide on the amount of platforms he will use, the height of the first platform, as well as the difference in height from one platform to the next. Camilla needs to decide on the length of material to cover each platform from the top to bottom, based on Kevin’s decisions (width does not matter). This task is to create two formulas that will calculate the height of the tallest platform and the total length of material in terms of the number of platforms, the height of the first platform, and the difference in height between adjacent platforms.

First correct answer is 10 points.

2007-09-10 20:13:50 · 2 answers · asked by David 3

2007-09-10 19:57:09 · 4 answers · asked by KUNDAN B 1

Please solve definite integral ∫x^2/(1+ e^sinx) dx from -2 to 2

2007-09-10 19:56:26 · 4 answers · asked by bilbo 3

increase in the height of the water level in centimetres ?

2) A rectangular box is 16cm long and 10cm wide. 960 1-cm cubes can fit into the box exactly. What is the height of the box ?

2007-09-10 19:42:05 · 5 answers · asked by Lim S 3

u/10 + u/5 = 6

u=?
whats u!?!?!?!

2007-09-10 19:24:38 · 5 answers · asked by Anonymous

1).solve for x.

3x-2y=6



2). solve.

-3(x+1)=2(x-8)+3

2007-09-10 19:17:40 · 8 answers · asked by moni 1

A rectangle has 3 sides of 3x-4 and 7x+10. Find the expression that represents its perimeter.

2007-09-10 19:10:44 · 5 answers · asked by lele 2

Given integral sqrt (1-4x^2 )dx, how would you answer the question?

substitute 2x = sin theta
x = 1/2 sin theta
dx = 1/2 cos theta
By formula, I get integral sqrt. (1-sin^2 theta) dx

then which is integral cos theta dx ? Do I sub in dx = 1/2 cos theta ?

If so, 1/2 integral cos^2 theta is what I get...yet I'm pretty certain that I'm not going about this in the right way.

Thank you for answering.

2007-09-10 18:59:14 · 3 answers · asked by J.W. 2

An individual has three coins randomly placed down on a surface.What are the odds all three will be tails after flipping two random coins three times each? I hope this makes sense! :)

2007-09-10 18:51:51 · 9 answers · asked by Anonymous

1. (5+1)+14=5+(?+14)





2. 5*4 divided by 2 -4^2=i got -6?

2007-09-10 18:51:48 · 10 answers · asked by lele 2

Basically this is a problem I've spent a while working on, and I can't seem to get the right answer.

f(x)=1/(x+3)

^^^Is the function, and I'm supposed to find the difference quotient. We have not really gone over secant/tangent lines yet, so just simplify it in:
[f(x+h)-f(x)]/h

If you could show all your steps, that would be most helpful
Any help would be greatly appreciated.

2007-09-10 18:47:51 · 2 answers · asked by Anonymous

If A is measurable then the translate A+x is measurable. How will I prove this one?

2007-09-10 18:35:58 · 2 answers · asked by MATHer 2

So it needs to be solved. 1/(x+1) + 3/(x-4) >(or equal to)
-1/2. The answer to the question is (- infinity, -5] u (1,2} u (4, infinity). I don't understand how to do it, a math lab person told me the 2 critical values are 1 and 4, but I don't think thats all there is. thank you so much for your help!

2007-09-10 18:28:02 · 4 answers · asked by mandy 2

i have the square root of the square root of 32

at first i thought that the 2 square roots would cancel giving me 32 as an answer but according to the back of the book its wrong?? Help please.

2007-09-10 18:22:39 · 9 answers · asked by lakai553 1

using 1, 2, 3, 4
and....
using parentheses ( ), decimal point '.' , and a minus sign '-'

create the largest number you can.

* you may only use the numbers once, but may use the symbols as many times as you want.

Please help me out, this is really baffling.
thank you so much.

2007-09-10 18:22:18 · 13 answers · asked by Julie 1

If f is a function, does f(s+t)=f(s) +f(t)

If X1f(X2)

2007-09-10 18:16:39 · 3 answers · asked by Anonymous

+F*cos(ϑ)-3000=0
+F*sin(ϑ)+1000=0

2007-09-10 17:43:31 · 4 answers · asked by Midlothian 2

2007-09-10 17:40:56 · 4 answers · asked by Evy 1

how would you find the standard form of an equation of a circle if only given the end points of a diameter?

endpoints of a diameter:(0,0) (6,8)

2007-09-10 17:29:30 · 9 answers · asked by yofosho 1

That is, I want to be able to enter the function and then get the derivative, and if this site solves integrals, that would be awsome!! .... I used to know one for free... but I can't find it anymore!! THANK YOU SO MUCH!!!

2007-09-10 17:23:57 · 2 answers · asked by StrawberrySmoothie 2