Mathematics - 6 December 2007

the questions is
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For which positive integer n will the equestions
(1) x1+x2+x3+...+x19 = n , and
(2) y1+y2+y3+....+x64 = n
have the same number of positive integer solutions?
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since C(n+k-1,k) = #ofsolutions,
i got
(19+n-1)!/19!(n-1)!=(64+n-1)!/64!(n-1)!

but i can't get anywhere then, was my approach wrong?
i hope somebody could help me,,,,at least some tip or hint.

2007-12-06 17:25:48 · 1 answers · asked by Anonymous

solve cos(x)=x
anyone who dos this step by step is a genius!!

2007-12-06 17:21:33 · 4 answers · asked by MTG G 2

x
8 =1

2007-12-06 17:18:22 · 2 answers · asked by Alexis O 1

(1+2x)=8
2

2007-12-06 17:17:07 · 5 answers · asked by Alexis O 1

A boat leaves a dock at 2:00 P.M. and travels due south at a speed of 10 km/h. Another boat has been heading due east at 20 km/h and reaches the same dock at 3:00 P.M. How many minutes past 2:00 P.M. were the boats closest together?

A farmer with 780 ft of fencing wants to enclose a rectangular area and then divide it into four pens with fencing parallel to one side of the rectangle. What is the largest possible total area of the four pens.

Area = ft^2

2007-12-06 17:14:39 · 1 answers · asked by iDontKnow 1

log x (4/5)=1

2007-12-06 17:14:10 · 2 answers · asked by Alexis O 1

What happens when you have this?

A empty set with a union of (4, 5, 6)

So, it looks like: (empty set) U (4, 5, 6)

Is this answer to this an empty set or nothing? or something else

2007-12-06 17:11:11 · 8 answers · asked by thunderbomb90 3

Find the point on the line that is closest to the point . (1,2)

Find the dimensions of the rectangle of largest area that has its base on the x-axis and its other two vertices above the x-axis and lying on the parabola y=4-x^2 . List the dimensions in non-decreasing order

last question : )
Find the dimensions of the largest rectangle that can be inscribed in a right triangle with legs of length 3 cm and 4 cm if two sides of the rectangle lie along the legs. List the dimensions in non-decreasing order.

2007-12-06 17:08:41 · 1 answers · asked by iDontKnow 1

I know how to isolate x, but i'm not sure how to isolate x if t's a fraction?: 4x = 8/4

Also, how do i solve this? 40 + ⅝?

Another thing, how do i turn a radical into a fraction? 40⅝

I appreciate your help!

2007-12-06 17:07:46 · 9 answers · asked by Mzee 3

math Q:all the whole numbers with a digit of 2 are written in increasing order. The list begins 2, 20, 21, 22 .... Find the 1000th digit thus written. The answers you can choose from are A)6, B)7 C)8 D)9.. explainn your answer.. good luck.!

2007-12-06 17:04:38 · 5 answers · asked by 27ysq 4

-6

2007-12-06 17:02:39 · 7 answers · asked by Ashley 1

I need to use the function q^2+n/2q where n is the number that I want to estimate the square root of. Apparently this was Newton's method of finding square roots, but I have no idea what to input for a q value in my excel sheet. Any idea?

2007-12-06 16:58:21 · 3 answers · asked by ifm2161 2

Given f(x)=3x+4

1. Is f(x) a function? Why or why not?

2. Find f -1(x).

Is f -1(x) a function? Why or why not?

2007-12-06 16:53:41 · 5 answers · asked by Ashley 1

2007-12-06 16:50:16 · 23 answers · asked by Jack M 1

1) Write the complex number (sqrt(3)/2)-(1/2i) in the form re^i(theta).

2) Write the complex number 2e^(-pi/4)i in the form a + bi.

3) Write the complex number e^(3+4i)t in the form a(t)+b(t)i.

2007-12-06 16:38:12 · 3 answers · asked by Victor 1

determine all of the values of x such that
sin^5x + cos^5x = 1 and 0 ≤ x ≤ π/2

2007-12-06 16:37:01 · 1 answers · asked by Anonymous

Find the outward flux of the vector field F = (x^3, y^3,z^2) across the surface of the region that is enclosed by the circular cylinder x^2 + y^2 = 36 and the planes z = 0 and z = 2.

Don't know how to do this

2007-12-06 16:36:59 · 1 answers · asked by dizayfashizay 2

This was a bonus question on my test that i know i got wrong. can someone please show me how to do with steps please.

ax^2+bx+c=0

thanks

2007-12-06 16:35:04 · 5 answers · asked by Dude 3

2007-12-06 16:17:48 · 6 answers · asked by Anonymous

better? lol

2007-12-06 16:17:05 · 8 answers · asked by Anonymous

2007-12-06 16:14:23 · 1 answers · asked by Anonymous

Solve the triangle: a = 5, b = 8, c = 12

I found three angles, but their sum come out to 94.11 when it should be 180.

Where am I doing it wrong? I used the law of cosine.

Thanks.

2007-12-06 16:08:49 · 4 answers · asked by labelapark 6

A plane is headed due east with an airspeed of 340mph. Its true course, however, is at 98degrees from due north. If the wind currents are a constant 55mph what are the possibilities for the ground speed of the plane?

2007-12-06 16:07:11 · 4 answers · asked by Anonymous

1.Five times the sum of twice a number and fiveis twenty-five. Find the number.

2. Sam is 45 years old, which is 20 less then 5 times Minnie's age. Which equation could be used to solve for Minnie's age. How old is Minnie? (Let Minnie's age be x)

2007-12-06 16:05:16 · 6 answers · asked by Anonymous

The question is this:

Find the linearization (linear approximation) of f(x) = ln(x) at a =1, then use it to approximate ln (0.98) and ln (1.05). Draw the linearization at a=1, are your approximations over or under approximations? Check on your calculator, how close are you?


I did the first part, I got y=x as the linear approximation. I just don't know how to use this to approximate ln (0.98) and ln (1.05). Would it be 0.98 and 1.05? I'm so confused. Please help! All work should be shown since I need to understand this completely and not just know the answer. Thanks in advance!

Also, I forgot the other question. It is as follows:

2. What function would you use to create a linear approximation for (8.06) ^ (2/3)? Approximate the value using linear approximation or differentials.

Now, I'm thinking that we know the value for 8^ (2/3) and it would just be (8 + x) ^ (2/3) but I'm not sure if this is right and what to do from here

2007-12-06 15:59:41 · 3 answers · asked by Anonymous

2007-12-06 15:51:37 · 6 answers · asked by bozza 1

1. Let {a_n} from n = 1 to infinity be a bounded sequence. For each n that is an element of the natural number set N, define
y_n = sup{a_k: k>=n}.

(i) Prove that {y_n} from n = 1 to infinity is decreasing and bounded from below, hence convergent.
(ii) Let A be the limit of the sequence {y_n} from n = 1 to infinity. Prove that {a_n} from n = 1 to infinity has a subsequence that converges to A.

2. Use item 1 to prove that every Cauchy sequence is convergent.

2007-12-06 15:49:43 · 1 answers · asked by Gabe 3

Prove that as k -> 0, the following expression reduces to 1/x:

(1/(k(k-√2))) ( (√2-2k)(√((1/2) + k√2 - k²) x - √(2k√2 - 2k² + x²) )

2007-12-06 15:47:41 · 1 answers · asked by Scythian1950 7

and that passes through the given point?

(-5,5); y = -5x + 9

(-1,-4); y = 1/6x + 1

i think the formula is y - y1 = m (x - x1)
but i'm not sure.


can you please explain to me how you do it?

2007-12-06 15:40:36 · 6 answers · asked by 소미 1

can someone show me how to do this

2007-12-06 15:37:00 · 1 answers · asked by Anonymous