Mathematics - 30 June 2007

where can I find the proof of the derivative of cos x = - sin x

2007-06-30 23:45:18 · 8 answers · asked by during 1

Given :-
1. Sin ψ = {(3)^(1/2)} * Sin Φ
2. Tan Φ = x2/2a
3. Tan ψ= x1/a
4. x3*x2 = x1*2*a
5. (x3+2a)/(x1+x2) =[ {(x3)^2 +2*a*x3}^1/2]/a

Here Φ , ψ , x1 , x2 , x3 are variables
and 'a' is a constant

Prove that x1+x2 = {(2)^(1/2)}*a

2007-06-30 23:21:16 · 1 answers · asked by Anonymous

2007-06-30 22:25:48 · 10 answers · asked by linga a 1

2007-06-30 21:42:13 · 5 answers · asked by Anonymous

2007-06-30 21:29:55 · 3 answers · asked by Anonymous

2007-06-30 21:10:46 · 10 answers · asked by dexter trimble 1

the number line for kindergartners has positive numbers going to the right of 0 and negative numbers to the left ..... why are the negative numbers on the left and the positive ones on the right ? because it really would not change anything if they interchanged places .... why aren't the negative numbers on the right and the positive ones on the left ... ?

2007-06-30 20:41:35 · 6 answers · asked by lukey7650 2

p= 20 / (q^2+5)

A) -10 / qp
B) -10/ qp^2
C) -5 / qp^2
D) -5 / q^2p

2007-06-30 19:43:03 · 3 answers · asked by tc 1

2007-06-30 19:30:44 · 4 answers · asked by Anonymous

A bag contains 5 red marbles, 7 blue marbles, and 10 green marbles. One marble is drawn at random. What is the probability that it will be either:

a. red or green?
b. blue or green?
c. red or blue?

2007-06-30 19:12:27 · 9 answers · asked by sweet_candy 2

The position vectors of two points A and B relative to an origin O are 3p-q and 2q-p respectively. Find, in terms of p and q, the position vector of the point C such that AC= 3BC.(AC and BC with the --> arrow on top u know what i mean)

2007-06-30 18:53:47 · 2 answers · asked by noobie 2

Consider the function f(x)=2x+9x^(-1). For this function there are four important intervals:(-inf, A], [A, B), (B, C] and [C, INF) where A, and C are the critical numbers and the function is not defined at B. Find A, B, C
For each of the following intervals, tell whether f(x) is increasing (type in INC) or decreasing (type in DEC). Find
(-INF, A], [A, B), (B, C] and [C, INF)
Note that this function has no inflection points, but we can still consider its concavity. For each of the following intervals, tell whether f(x) is concave up (type in CU) or concave down (type in CD). Find (-INF, B), and (B, INF)

2007-06-30 18:32:53 · 2 answers · asked by Anonymous

A rancher wants to fence in an area of 1500000 square feet in a rectangular field and then divide it in half with a fence down the middle parallel to one side. What is the shortest length of fence that the rancher can use?

2007-06-30 18:20:29 · 5 answers · asked by Anonymous

A) 4(16+x^-6) / (x^3)
B) 3(4x^3+1) / (x^3)
C) 3(16x^6 -1) / (x^4)
D) 4( 16 - x^-6) / (x^3)
E) 3(4x^6-1) / (x^3)

2007-06-30 18:10:22 · 2 answers · asked by tc 1

2007-06-30 17:27:12 · 7 answers · asked by That Other Guy 1

A goat is grazing in a circular field with a rope attached to it of length r. The goat is free to eat all the grass as it moves around in the circular field and the area of the field is obviously pi.r^2.
Question - How long is another piece of the rope if it is now fixed to a point on the circumference of the circle and the goat can now only eat 50% of the grass in the original circle.

2007-06-30 16:53:20 · 6 answers · asked by Anonymous

Nielson Media Research wants to estimate the mean amount of time (in minutes) that full time college students spend watching television each weekday. Find the sample size necessary to estimate that mean with a 15-minute margin of error. Assume that a 95% confidence level is desired. Also assume that a pilot study showed that the standard deviation is estimated to be 112.2 minutes.

2007-06-30 16:49:23 · 1 answers · asked by heffie130 1

The slope of a line is zero. What is the slope of the line that is parallel to it?

0

1

undefined

not enough information

2007-06-30 16:01:01 · 10 answers · asked by Anonymous

I was looking at my old guinness book of world records and oh of the pages was, " R. E. Hughes reached record
weight of 4,763 N.".
And that didn't do any thing for me...I searched wikipedia and goodled his name, but nothing came up.
Can some one give me that number in kilograms?

2007-06-30 16:00:14 · 2 answers · asked by Scooby Snacks 2

The slope of a line is two-thirds.
What is the slope of a line that is perpendicular to it?

negative three-halves

negative two-thirds

three-halves

two-thirds

2007-06-30 15:58:09 · 9 answers · asked by Anonymous

Intersecting lines are perpendicular.

Always

Sometimes

Never

Not enough information

2007-06-30 15:52:31 · 5 answers · asked by Anonymous

The purchasing manager for a firm is trying to determine what the safety stock should be for a particular product. She has developed the following table, which gives the distribution of demand during the lead-time and the probabilities:

Demand during lead time / probability
40/ 0.2
50/ 0.25
60/ 0.25
70/ 0.2
80/ 0.1
The carrying cost is $5 per unit per year, the ordering cost is $30 per order, and the stockout cost is $40 per unit. The reorder point is 60 units, and 6 orders are placed each year. What level of safety stock should be maintained?
ROP (reroder point)=d (daily demand) x L (order lead time) +SS (safety stock)
I don't know how to solve it.

2007-06-30 15:44:31 · 2 answers · asked by Anonymous

2007-06-30 14:10:01 · 5 answers · asked by Anonymous

Please show your work.

2007-06-30 14:06:26 · 3 answers · asked by Anonymous

Find the midpoint between the points (3, 0) and (-1, 4).

(2,2)

(1,2)

(1.5,1.5)

(1.5,-2.5)

2007-06-30 13:48:23 · 6 answers · asked by Anonymous

Am I correct in thinking that angles will reach their maximum range at 45 degrees....therefore, when applying this concept to projectile motion problems, one should...

...take the original angle provided-for example 60 degrees-double it, and find the difference between 60 doubled (120) and 45 doubled (90); 120-90=30; therefore, the angle from which an alternative projectile can be shot to arrive at the same horizontal point is 30 degrees??

...This is how I understood someone's explanation to another physics problem that I asked (thanks to the person who took the time to answer!)...

...Anyway, I wanted to make sure I understood this concept correctly...does this apply to all angles from which projectiles are shot??

Thank you!!!

2007-06-30 13:05:35 · 5 answers · asked by Anonymous

can anyone tell me what i need to do to evaluate the integral of (4x-3)^9dx tell me exactly what ur doing please

2007-06-30 12:56:40 · 7 answers · asked by raleighzia 1

I have looked everywhere and can find random sample but not non random sample.

2007-06-30 11:13:54 · 6 answers · asked by tara-can you 1

The problem is-

A car leaves San Fransisco heading towards Denver going at the constant speed of 50 miles per hour. Another car leaves Denver heading towards San Fransisco an hour later, but going at a constant speed of 60 miles per hour. When the two cars meet, which car is closer to Denver?

Its a trick question in real life, but if you wanted to solve it, could you? If so, how?

2007-06-30 11:03:32 · 6 answers · asked by Anonymous

His actual speed 6 miles an hour but I have no idea how to get to it. Can someone explain it to me? Thanks.

2007-06-30 11:02:42 · 4 answers · asked by Mayoku 2