Mathematics - 23 October 2007

Okay like i get you first find the derivative of the terms provided, but where do you put dy/dx? is it when you find the derivative of y you automatically put dy/dx to be mulitplied to it right? like for example.......xy+y^2=2 get x(dy/dx)+y+2y(dy/dx)=0 after isolating it and everything i get -y/(2y+x) is this right?
IF soo.... Im asked to find the second derivative of it...so after i use the quotient rule i get (2y+x)(-1)-(y+1)(-y)(dy/dx)/(2y+x)^2 if thats right how come i put dy/dx by the derivative of g(x)? can someone please help me out? i really really appreciate it

2007-10-23 15:13:43 · 3 answers · asked by Anonymous

2007-10-23 15:11:37 · 3 answers · asked by argentina_mandy20 1

The average of four odd integers is 34. Find the integers.


I need to know the steps.

2007-10-23 15:11:34 · 5 answers · asked by apetkw 2

- Find the inverse of f.
- What are the domains and ranges of f and f^-1?

1. f(x) = (x+5)/(x-4)

My answer:

f^-1 (x) = (4x + 5) / (x-1)

Domain of f and range of f^-1 = (- inf , 4) U (4, inf)
Domain of f^-1 and range of f = (- inf , 1) U (1, inf)

2. f(x) = x^2 -2, x
My answer:

f^-1 (x) = sqrt (x + 2)

Domain of f and range of f^-1 = (- inf , 0 ]
Domain of f^-1 and range of f = [ -2 , 0 )

Am I right? Thanks.

2007-10-23 15:09:46 · 1 answers · asked by labelapark 6

2007-10-23 15:06:10 · 5 answers · asked by jjfine96 2

2007-10-23 14:52:55 · 9 answers · asked by wat 1

Solve exactly and approximately to 3 decimal places.

1. log 3 (x+5) + log 3 (x-3) = 2

Log 3 is log base of 3.

My answer: x = 4

2. 3^(5x-1) = 81

My answer: x = 1

3. 2log 2 (3x+2) - log 2 (x) = 6

Log 2 is log base of 2.

My answer: x = 2^(3x-4)

4. 3^(4x-3) = 100

My answer: x = (ln 100 + ln 3 (3) ) / ln 3 (4)
x = 1.7980

5. log 5 (x+8) + log 5 (x+4) = 1

log 5 is log base of 5

My answer: x = - 3


Am I right for these? Thanks.

2007-10-23 14:48:29 · 3 answers · asked by labelapark 6

2007-10-23 14:41:18 · 3 answers · asked by JESS 1

If n^2≠n mod 3, then n ≡ 2 mod 3.

2007-10-23 14:37:34 · 2 answers · asked by bandit8711 1

Let A, B, and C be subsets of the universal set U. if A∩compliment of B=A,B – C=B, and (AUB) ∩C=C, then C is in the subset of A.

2007-10-23 14:36:41 · 1 answers · asked by bandit8711 1

2007-10-23 14:28:47 · 2 answers · asked by MareK D 1

-5+4a(6+8)-1

2007-10-23 14:24:46 · 16 answers · asked by Anonymous

State what is meant by a subgroup of a group?

2007-10-23 14:23:14 · 4 answers · asked by Anonymous

2007-10-23 14:16:47 · 8 answers · asked by Anonymous

How do I find the distance between two longitude/latitude points?
I need to know how to find the distance between the two points
(60N, 110W) and (20S, 110W)? Can someone please help me

I need to know the actual method (i.e the formula or conversion to use) not just the answer... :) thanks

2007-10-23 14:15:24 · 2 answers · asked by Albus 2

i'm stumped and i need this for my homework which is due tomorrow.

thanks to anyone who answers

2007-10-23 14:08:53 · 8 answers · asked by Anonymous

Prove that
n
∑ (-1)^i * nCi * (k – i)^n = n!
i=0

where i, n, k Є Z+

2007-10-23 14:04:15 · 5 answers · asked by Dr D 7

in example 3, we chose vector c and let vector c = sa+tb. (a + b are vectors. Then we found that c= 2a + 3b. what result would we have obtained if we had chosen:

a) b instead of c??

(((( the coordinates from example 3 are a=[1,2,3], b=[2,.1,3] and c=[8,1,15] )))))

the answer is b= -2/3a + 1/3c.


can someone show the work i keep getting it wrong even though i follow the exmaple exactly!!

2007-10-23 13:59:20 · 1 answers · asked by mystery_girl07 2

The sum of a number and 6 times it's reciprocal is -7. Find all numbers that meet this condition.

Be sure to list all the solutions.
If there are multiple solutions, separate them with commas, but do not include any spaces in your response.

2007-10-23 13:58:49 · 5 answers · asked by ry ry 3

x+4y-z=10
-2x+3y-2z=7
3x+2y+z=4


I have gotten 3 different answers.. the answers work for 2 of the equations but not all three.. can someone help??

2007-10-23 13:58:44 · 3 answers · asked by Anonymous

2007-10-23 13:53:47 · 2 answers · asked by james p 2

So I am struggling with this question (the 4 rpm thing is throwing me off):

"A lighthouse is located on a small island 3 km away from the nearest point P on a straigh shoreline and its light makes four revolutions per minute. How fast is the beam of light moving along the shoreline when it is 1 km from P?"

So far I have drawn out the right triangle and made the angle between the beam of light and the perpindicular theta. Made the verticle line (perpindicular to the shore) 3 km, and the shore "x". I think I should be solving for dx/dt? Anyway, I've used "tangent theta = x/3" to relate everything. Made that into x = 3 tangent theta, took the derivative, and solved for dx/dt (after calculating theta). I came up with 38.317.... but I don't know the units and I'm pretty sure it is not correct. Any help would really be appreciated.

2007-10-23 13:50:12 · 1 answers · asked by RedBirdNation 2

If log2(log3a)=2, determine the value of a. (Answer:81)

Note: The 2 after the first log is a subscript as well as the 3a after the second log.

If log2n(1994) = logn(486sqr2), determine the value of n^6.
(Answer: 2.23 8 10^11)

Note: The 2n after the first log is a subscribt and the n after the second log is also a subscribt. Also note that the 2 is squarerooted.

Please show all the steps. It would really help!!

2007-10-23 13:43:35 · 1 answers · asked by Sandra 2

2007-10-23 13:42:09 · 3 answers · asked by ggmal8 2

1. Prove that if G=, then G=

2007-10-23 13:40:14 · 1 answers · asked by Anonymous

how many marbles does each have?

2007-10-23 13:35:12 · 8 answers · asked by Therry 2

Where I live we have rent control and it's 8%.
In February my rent will go up 8% from $900.00 and I would like to know what it will be but I don't know how to figure it out.
So could you please tell me what 8% of 900 is?

2007-10-23 13:33:07 · 5 answers · asked by Adelaide B 5

need help with this.
i can do this in my head.
but teacher want us to show work.
need to find two numbers.
the long way. show me how oyu got it.

2007-10-23 13:30:31 · 4 answers · asked by bonecca133 1

6x-2=x+1

please help me

2007-10-23 13:29:10 · 5 answers · asked by Anonymous

Please help me on these! ive been stuck on them all week! Please show me how they are done too so i can learn too.

1. A child was born in Boston, Massachuesettes, to parents who were also born in boston. The child is not automatically a US citizen, how is this possible?


2.What is the 99th letter in the pattern below?

ABBCCCDDDDEEEEE...


3. In how many ways can you make change for $20 using only quarters and dimes, with atleast one of each coin used?


4. The number 1961 has rational symmetry, because the number looks the same when turned 180 degrees, find the next greatest number that also has this feature.


5. Show how half of 13 can possible be eight.

6.How mcuh money would you make in 8 days if you made 8 dollars everytime the hands of a clock formed a 90 degree angle?

Please try and answer as many as possible and THANK YOU SO MUCH!!!

2007-10-23 13:28:03 · 6 answers · asked by Anonymous