Mathematics - 19 December 2007

is x^3 + y ^3 = (x+y)^3?

x^3 + x^4 =? is it possible to simplfiy?

2007-12-19 09:05:24 · 6 answers · asked by samkill 1

please help and explain?

find the roots of
1) 10x^4 + x^3 + 7x^2 + x -3 = 0

a. -3/5, 1/2; +/- i
b. 3/5, -1/2; +/- i
c. -2/3, 3/4; +/- i
d. -1/3, 3/4; +/- i


2) x^4 - 7x^2 + 12 = 0

2007-12-19 08:40:58 · 1 answers · asked by anna 1

How would I "Express in terms of a single angle (x)" for cos(3x) and sin(4x)?

So far for cos(3x), I have:

cos(3x) = cos(2x + x)
= cos 2x cos x - sin 2x sin x
= (2 cos ^2 x - 1)cos x - 2sin^x cos x
...and then I'm lost

As for sin(4x), I have down...
sin(4x) = sin (2x + 2x)
= sin 2x cos 2x + cos2x sin 2x
= 2 sin 2x cos 2x
= 2 (2 sinx cosx) (cos^2 x - sin^2 x)
...and that's all I have for that.

There's several formulas for cos (2x) and sin (2x), but I have no idea which to use. Any help would be great.

Thanks.

2007-12-19 08:36:01 · 5 answers · asked by Thunder 2

Hi I need to know what the difference is between haveing one variable and having three variable? I Know the way it is worked out will be diferent for all three but I am having a problem explaining it to my little sister. Please Help. Thanks

2007-12-19 08:33:49 · 1 answers · asked by .... 1

Let segment AP be an altitude of triangle ABC, and let segment DQ be an altitude of triangle DEF. Prove that if AP=DQ, then the area of ABC / area of DEF = BC / EF. In words, prove that when two triangles have the same altitude, their areas are in the same ratio as their bases.

2007-12-19 08:30:28 · 3 answers · asked by harrypotteressence 3

a. 35 mi/hr * 5280ft/1 mile * 60 min/1 hr
b. 35 mi/hr * 1 mile/ 5280ft* 1 hr/60 min
c. 35 mi/hr *5280ft/1 mile* 1hr/360sec
d. 35 mi/hr * 5280ft/ 1mile* 1hr/3600sec
e. none of the above
, im so lost help!

2007-12-19 08:27:56 · 8 answers · asked by Kristen V 1

I can't seem to work through these proofs. Please help.

1) sin2x = 2cotxsin^2x

2)(sin^2x)/(sin^2x) = 4-4 sin^2x

3)cos^4-sin^4x= cos2x

4)cos^2 2x+4sin^2xcos^2x = 1

2007-12-19 08:09:47 · 4 answers · asked by TDK 1

( ^ = to the power of )

Write the product as a trinomial

(p^2 – q^2)(p^2 + 3q^2)

it can be

p^4 + 2pq^2+ 2q^2
or
p^4 + 4p2q2 – 3q4
or
p^4 + 2p^2q^2 – 3q^4
or
p^4 – 4p^2q^2 – 3q^4


thank you!!!! ;)

2007-12-19 08:03:17 · 12 answers · asked by Anonymous

( ^ = to the power of )

it can be

6x^2+5x – 6
or
6x^2+13x – 6
or
6x^2– 5x – 6
or
6x^2– 13x – 6


thank you!!

2007-12-19 07:54:53 · 7 answers · asked by Anonymous

do we leap to catchup or leap to go ahead?

2007-12-19 07:41:06 · 6 answers · asked by Prophet 1102 7

1) A subset of R which is meager in Baire classification and has positive measure;

2) A subset of R with has null measure but is not meager.

Thank you

2007-12-19 07:08:23 · 1 answers · asked by Anonymous

a train is coming from Chicago at 150 mph and slows down 2 miles per hour each minute it leaves at 5:00 am
a train is coming from New York at 150 mph gain 2 mph each minute it leaves at 2:00 pm if these 2 train follow the tracks at what time will they meet?

2007-12-19 07:04:08 · 5 answers · asked by Anonymous

At the homecoming football game,the senior class makes $1.50 for every program sold. Describe the direct variation for the amount of money the senior class will make from selling football programs.

2007-12-19 06:54:06 · 6 answers · asked by Anonymous

2007-12-19 06:52:26 · 3 answers · asked by malkana d 2

please help me asap! It would be greatly appreciated!

2007-12-19 06:50:15 · 3 answers · asked by Anonymous

Find an equation of a parabola (in general form Ax^2 + Bx + C) with vertical axis, vertex at (2,1), and passing
through (1,3). What what is A + B?

I know that y=a(x+h)^2 + k and (h,k) is the vertex but I dont know how to find A and B and how the general form relates to the standard form (y=a(x+h)^2 + k).

Thanks
Chris

2007-12-19 06:44:03 · 2 answers · asked by alanone88 1

Please SHOW THE WORK!!!

2007-12-19 06:40:44 · 4 answers · asked by Anonymous

2007-12-19 06:39:19 · 5 answers · asked by Anonymous

A certain recipe calls for 2 cups of milk for every 3 cups of flour. If 2 cups of flour are used, how many cups of milk should be used?

and also,

an ear of corn cost 20 cents last year and 30 cents this year. by what percent has the price increased?

thanks....

2007-12-19 06:37:25 · 4 answers · asked by cat 2

55) Which of the following has a graph that is symmetric to the x-axis?

y = x
y2 = x
y = x3 - x
y = x2 + 3


What is the answer to the question and why? Can you please explain to me how to do these types of problems??

EASY 10 POINTS!!

2007-12-19 06:23:45 · 8 answers · asked by GJ 2

The arcs will either be all convex inward or all concave inward and the inscribed circle must be exactly touching all three arcs. I can get close using AutoCAD and the "trial and error" method, but it seems that there would be a formula or a drafting procedure that would make it simple, quick and accurate every time. If there are any math geniuses out there, consider this a challenge. I have not been able to solve this for a few days now.

2007-12-19 06:14:15 · 3 answers · asked by Anonymous

Why not just work with everything in degrees? Why are radians so much better in higher level math. I use radians all the time, but I just don't see the big deal.

2007-12-19 06:12:53 · 4 answers · asked by de4th 4

PQR is parallel to BC and XC is a straight line. QCB [angle c]=62 degrees, XBC[angle B]=15degrees and BPQ[anglep]=110degrees
Calculate:
(i)RQC....[angleq]
(ii)PBX....[angle b]

2007-12-19 06:12:36 · 2 answers · asked by bubble 1

I've been studying for a math final coming up and I'm not sure how to do this. If someone could explain it out to me, it'd be much appreciated!!!

2007-12-19 06:06:03 · 6 answers · asked by hmm 3

22.1 minus 16.0 over 16.0?

2007-12-19 06:03:50 · 4 answers · asked by Josephine K 1

a wedge ABCDEF has a perpendicular to the plane FEDC with measurements BC=5cm,CD=12cm,DE=13cm
Calculate:
(i)the length,in cm,of BD
(ii)the surface area,in cm2,of the wedge
(iii)the volume,in cm3,of the wedge
(iv)the size of angle BDC

2007-12-19 05:56:33 · 3 answers · asked by baby 1

the internal dimensions of a saucepan shaped like a cylinder are height 20cm and diameter 35cm. Calculate to the nearest whole number,
(i)the area,of the bottom of the saucepan
(ii)the largest volume of liquid,in cm3,which the saucepan can hold.

2007-12-19 05:53:09 · 3 answers · asked by baby 1

I'm braindead, help me out.

2007-12-19 05:51:52 · 4 answers · asked by WHAT THE HELL 4

1.Solve for x: √(3x - 5) = 4 ?
2.Solve for x: √(3x+1)-√(x-1) =2 ?
3.-3 - √(3x+1) = 0 has no roots. (true or false)?
4.3 + √(3x+1) = x has two roots.(true or false)?
5.Solve for x: √(x + 12) = x ?
6.Solve for x: √(x - 5) = -1 ?
7.Solve for x: √(x2+ 64) =16 -x ?
8.Solve for y: √(2y+ 7) - √(y + 4)= 2 ?
9.The solution of √(x + 11) = x- 1 is -5.( True or False) ?
10.The solution of √(x + 11) = 3 is -2. (True or False )?
11.Solve for x: √(x2+8x) =4√3 ?
12.Solve for x: √(5x + 1) = √(4x + 1) ?
13.Solve for x: - √(x) = -1 ?
14.Solve for x: x + 1 = √(x + 7) ?
15. √(x + 1) +3 = 2 has no real roots.(True or False )?
16.Solve for x: √(x2-x + 5) =5 ?
17.Solve for x: √(2x2+ 7x ) -2 =x ?
18.Solve for x: x - √(2x + 1) =7 ?
19.Solve for y: 4 + √(5y + 1)= 0?
20.√(x 2+ 3x + 2) = -4 has no real roots. ?
21.Solve for x: 2√(x - 3)+ 6 =x ?
22.Solve for x: √(x + 10) =7 -√(x - 11)?
23.Solve for x: √(x2+ 4x - 1) =√(x - 3) ?
24.Solve for x: √(x+16)-√(x) -2 = 0 ?

2007-12-19 05:47:19 · 3 answers · asked by Daniel P 2

5x^2+2y^2-20x+24y+82=0

2007-12-19 05:45:55 · 2 answers · asked by Bashir B 1