Mathematics - 28 November 2007

Show work! Hurry!!!!!

2007-11-28 16:49:22 · 2 answers · asked by Scythian1950 7

2007-11-28 16:38:07 · 9 answers · asked by Allison L 1

Suppose (X,Y) has joint density
f(x,y) = 2/x * e^(-2x) for 0

2007-11-28 16:34:02 · 1 answers · asked by cornzxo1 1

2007-11-28 16:33:42 · 6 answers · asked by Mango Muncher 6

0.000056 in scientific notation? plz include how you did this thanks :)

2007-11-28 16:33:14 · 6 answers · asked by Anonymous

2007-11-28 16:33:08 · 4 answers · asked by EP 2

I know its x___y times 100
y

I need help. example..... what is the percentage change of 148 and 152. thanks

2007-11-28 16:30:37 · 2 answers · asked by urban pharmacist 2

If you can find them the titles are Luchin It by Jean Hannagan and Understanding U by David Johnson from the Dell Math Puzzles and Logic Problems Magazine. I need he answers bad b/c I think mine are all off.

2007-11-28 16:28:45 · 1 answers · asked by DoINg BeTTeR 3

can someone explain how to factor. i just dont get it at all.
for example how do you do this problem?

2x^2 - 9xy + 7y^2

^ means its an exponent.

2007-11-28 16:28:07 · 9 answers · asked by california1991qt 1

2007-11-28 16:23:09 · 4 answers · asked by Anonymous

A car traveling at 48ft/sec decelerates at a constant 4feet per second squared.

Let denote f(x)the position function seconds after the decelerating process started. Then . f(0)=0
What is f'(0)? Answer:

What is f''(x)? Answer:

Use the above information to find f'(x)

Then, use f(0)=0 to find f(x)

How many feet does the car travel before coming to a complete stop?

Answer:

2007-11-28 16:21:24 · 4 answers · asked by scott b 1

Four people are to be selected at random from a group of four couples. In how many ways can this be done, given the following conditions?
a. there are no restriction.. i got this to be.. 8 C 4 = 70
b. the group must have at least one couple..
c. each couple must be represented in the group.

i don't know how to do b and c... can anyone help

2007-11-28 16:05:05 · 7 answers · asked by linh 1

??

2007-11-28 16:00:56 · 3 answers · asked by Anonymous

Trig problem I need help with.
How can I prove this expression. Please help me!!

2007-11-28 15:57:13 · 2 answers · asked by anthony c 2

Let the &'s be radicals because i can't find how to type it in my computer.

^3&320& + ^3&1250&
-----------------------------------
2 ^3&5&

How can i get rid of the radical on the bottom?

2007-11-28 15:55:50 · 1 answers · asked by basketcase 2

The problem is..... cos(sqrt[x])/sqrt[x]

I have tools that can show me the final answer, but I would like to know how it is done step by step. I dont see the point in knowing the answer without actually knowing how to get there.

2007-11-28 15:52:03 · 6 answers · asked by Anonymous

How do you prove the diagonals of a rhombus are perpendicular?

On this problem I have determined the points should be (0,0),
(a,0) (b,c) and (b+a,c). I have also found the slopes of the diagonals to be c/b+d and c/(b-d). But I don't what to do after this. I think you would prove that c^2 = a^2 - b^2 using cross multiplication on the slopes, but why would you want to prove this? I thought that opposite reciprocal slopes signify perpendicular lines; does this signify that too?

2007-11-28 15:50:00 · 2 answers · asked by Nathan 3

Jake, Mel, and Annie went mountain biking on Mammoth Mountain. Each biker took a different trail. They biked for a total of 10 hours and 10 minutes. Mel biked 2/3 as long as Jake and Annie biked 30 minutes less than Jake did. How long did each of them bike?

This is the question. I know it can be solved with Guess and Check, but I need the algebraic way, and FAST!
Please don't tell me to solve it myself, because I have no idea for the technique. Please post the walkthrough and the once-over of the question on your answer.
Thank you SO much for answering this question! First decent answer posted with a clear description and why you did so and so, will be best answer.
May the best person win!
(I need the answer in a day, due Friday)

2007-11-28 15:48:11 · 6 answers · asked by Seashells 2

affect how fast it will germinate. I have done 6 trials. for each trial there were 3 cups i tested. 1s got no water, 2s got water once a week, and 3s got watered ever day. I realized that groups 2 and 3 germinated between 4-6 days. I got the data, but how do i make a data table for that? and how and what kind of graph would i make?

2007-11-28 15:46:49 · 1 answers · asked by Escape 1

2007-11-28 15:42:01 · 2 answers · asked by subrat p 1

2007-11-28 15:41:07 · 9 answers · asked by CARLOS L 2

y = (x - 5)(x + 3)


I think the answer is -4 or 8. But I may be wrong. Help is highly appreciated. :)

2007-11-28 15:37:36 · 3 answers · asked by dumbhoe 1

OK, Let w(m) give the weight of an avg. sized baby girl who is m months old.

2. An 8-month baby girl weighs w(13) pounds. Is she of avg. weight, above avg., or below avg.? Justify your answer....and yes...it IS w(13) pounds...definately.

Ok, I pretty much think this is an inverse but I have absolutely no clue on how to solve it...HELP!

So far I've gotten all three here so I need the right answer...I'm leaning towards overweight but not sure...

can u explain in kinda detail why too?


THANKS!!!

2007-11-28 15:32:45 · 5 answers · asked by Anonymous

i tried and i got -4sin12x-3cos12x, but i dont think its right. after you get the differentiation, could you set it to 0 and solve for x? and show the steps? i completely forgot how to do trig but i think this will help. thanks!

2007-11-28 15:20:55 · 1 answers · asked by Anonymous

6^(2n-1) + 1 prove its divisible by 7. (please note that the +1 is not in the power (2n-1) )

Base case (n=1) 6^(2(1)-1) +1 = 7/7 = 1
since its an integer the base is satisfied.
Now assume the property holds for n=k such that 7 divides 6^(2k-1) +1.
Now let n=k+1

6^(2(k+1)-1) +1 ---->
6^(2k+2-1) + 1 = ?? im lost here...

2007-11-28 15:20:09 · 6 answers · asked by Ray 3

what is the answer to this (√2+√3)*(√2-√3)
and explain please because i don't get it

2007-11-28 15:18:28 · 10 answers · asked by Anonymous

the length and width of a rectangle are 6m. by 4m.. when each dimension is increased by the same amounth, the area of the new rectangle is 50 m (squared)...... solve it in quadratic form....

2007-11-28 15:18:22 · 1 answers · asked by desu_shigaisen 1

f(x) = (2+x^2) /( 1 +x^2)

2007-11-28 15:12:53 · 3 answers · asked by Anonymous

I am trying to find the answer to this integral problem

9 dx
-------
xln3x

I had a previous question that was the same but the answers were incorrect...
I'm completely lost when it comes to integrating fractions, could someone give me a boost?

2007-11-28 15:12:40 · 2 answers · asked by ret80soft 1

x^4-13x^2+36=0
i got x^2- 6.5x=-36
then i needed to square the 6.5 but I don't have a calculator..

Formula -(b)+-RARICAL (B^2-4ac)/(2A)
3x^2-6x=24
a.3
b.6
c.-24
I got 22 and 12

write 4 and -1 in quadratic formula
I got (x-4) (x--1)

2007-11-28 15:08:44 · 2 answers · asked by Anonymous