Mathematics - 30 December 2007

I think (i just think) its using this formula but i'm not sure how to get the answer: (a+b)^3=a^3+b^3+3ab(a+b)

the anwer is supposed to be : l^3+m^3+3l^2m+3lm^2

2007-12-30 23:59:58 · 8 answers · asked by Anonymous

OK this is the final one. Question is:

What is the greatest prime factor of (4^17) - (2^28)?

Answer is, apparently, 7.
Again there is a VERY long way of working this out but there must be a short cut. There's obviously some relation between 4 and 2 when powered up (?!) but I can't get all the way to the answer.

Multo thanks.

2007-12-30 23:41:23 · 7 answers · asked by Anonymous

I have noticed in my fumblings around the world of mathematics some funny things with square roots. For example:

(sqrt of 72) * pi = 6 * (sqrt of 2) * pi

I can see that something is happening here with factors of 72 but can't quite get my brain around what.

Pls advise. Many thanks.

2007-12-30 23:37:19 · 6 answers · asked by Anonymous

Whats the best way to divide large numbers?

Basically this is my question:

A new car costs £13500. The dealer gives a discount of £1282.50. What is the percentage discount?

Now the formula to work this out would be:
13500/1282.50 x 100 = %

But im stuck on dividing it. I cannot use a calc for this question. Would i multiply the both numbers again by 100 to remove the decimal, convert them to a fraction and simplfy them, and work on the division using a smaller number?

Thanks guys and girls.

2007-12-30 23:34:57 · 6 answers · asked by James J 1

Ordinary numbers

2007-12-30 23:31:32 · 38 answers · asked by Anonymous

If I have two equally proportioned triangles (same angles, ratio of sides etc), if the area of one triangle is TWICE that of the other, what is the length of the base (S) of the large one in terms of the smaller (s).

I'm presuming triangle shape is immaterial; it's just that they're equivalent and one is 2x the area of the other; and presumably the answering equation relates to any of the sides you'd wish to compare.

The answer is S = (sqrt of 2) x s.

But how do I know this? Pls advise how I could have worked it out. I have no further data (ie about height etc).

Thanks.

2007-12-30 23:26:39 · 5 answers · asked by Anonymous

would remain after 30.0 h has elapsed?

2007-12-30 23:22:22 · 3 answers · asked by Anonymous

don't you think it's beautiful to can speak in mathematical terms and be understood by everyone? I think that math is the most important universal language...and I wish one day I can study and work in reserarch maybe out of my land (sardinia)...
sorry for my bad bad english...
the question is: do you appreciate the universality of mathematical language?
bye...and happy new year from sardinia!!

2007-12-30 23:17:43 · 7 answers · asked by Sally Brown 3

Write each expression as a sum and/or difference of logarithms. Express powers as factors.

(1) log_3 (x/9)

(2) log_7 (x^5)

NOTE: log_3 means "log base 3" and log_7 means "log base 7."

Got it?

2007-12-30 22:05:42 · 4 answers · asked by journey 1

Use rules of logarithms to write each log in terms of a and b if In2 = a and In3 = b.

(1) In 27

(2) In fourth root of {2/3}

2007-12-30 22:01:46 · 2 answers · asked by journey 1

2007-12-30 21:34:17 · 10 answers · asked by rajarao_mamidi 1

x - y = 7 and 2x^2 - 3y^2 = 5

THANKS.. i'll give BEST ANSWER....

2007-12-30 21:32:33 · 4 answers · asked by nobody 2

im having my front room tiled after the new year and was wondering how many tiles i will need:

size of frontroom is 21ft long by 11ft 2", the tiles are 1ft by 1ft square...how many tiles will i need?

thank you. (im not too good on maths)

2007-12-30 21:17:51 · 6 answers · asked by tracieisland 5

Ans= [n(n-1)/2] + 1

2007-12-30 21:12:46 · 4 answers · asked by ʞzɹәႨnɹ 2

if u r given 'n' rods of length{1,2,3,4.....n} respectively.
what is the maximum no. of triangles that can be formed using these rods at a time?
one rod can be used only once.........
for example if n=5 , the max. no. of triangles formed will be 1..........using the combination(3,4,5)

2007-12-30 21:07:32 · 9 answers · asked by azhariitk 1

Culd someone help me please? thanks.

2007-12-30 20:59:04 · 6 answers · asked by Anonymous

The standard circle equation for is (x-h)^2+(y-k)^2= r^2

2007-12-30 20:32:13 · 3 answers · asked by Anonymous

2007-12-30 18:54:20 · 2 answers · asked by yuvraj singh sengar 1

simplify 2008 + 2007

2007-12-30 18:13:07 · 7 answers · asked by kevin jonas 2

If I get one wrong can you tell me the right answer and maybe the steps you took to get there, thank you.

GIVE EACH ABSOLUTE VALUE

i= imaginary number
I...I absolute value brackets

1.
I 8 - 6i I
A: square root of 28

2.
I -1 I
A: 1

3. I -12 + 22.5i I
A: square root of 362.25

4.
I 19i I
A: 19

ADD EACH PAIR OF COMPLEX NUMBERS

5. ( 2 + i ) + (-3 + 2i)
A: -1 + 3i

6.
( -5 + 4i ) + 3
A: -2 + 4i

7.
( 6 - 3i ) + ( -4 - 2i )
A: 2 + 5i

GIVE EACH ABSOLUTE VALUE

8.
I 15 + 7i I
A: square root of 274

9.
I -2 - 6i I
A: 2i times the square root of 10

10.
I square root of 8 - i times the square root of 4 I
A: Can you show me the steps on how you got this one, thx

11.
I 0.2 + 0.8i I
A: square root of .68

12.
I -14 I
A: 14

13.
I -3.6i I
A: 3.6

14.
I 20 + 21i I
A: 29

15. I -30 - 5.5i I
A: 30.5

ADD EACH PAIR OF COMPLEX NUMBERS

16.
( 3i ) + ( 8 )
A: 3i + 8

17.
( -4 - 3i ) + ( 2 - 2i )
A: -2 - 5i

18.
( 3 + 3i ) + ( 3 - 3i)
A: 6

19.
( 2 + 3i ) + ( 3 + 2i )
A: 5 + 5i

2007-12-30 18:12:17 · 2 answers · asked by Anonymous

-Area=56.52
-Use 3.14 for pi
-Tell me the steps on how to do this problem please!!
************THANK YOU IN ADVANCE*****************

2007-12-30 18:10:53 · 9 answers · asked by Anonymous

2007-12-30 18:01:16 · 3 answers · asked by footballcrazyshikharr 1

Ok, I have 3 16oz bottles and a 2 QT bottle. If I made the 2QTs of kool-aid would it fit in to the 3 16 oz bottles? How much would be left?

2007-12-30 17:54:35 · 2 answers · asked by Braedyn is due 5/8/08! 2

Sequence has no mathematical formula but it has some formula for its terms, easy to get it by observation, please.
If nobody answers correctly, one of the correct answers (both the blank spaces filled) will be posted here at the last moment to have fun and feelings.

2007-12-30 17:34:32 · 9 answers · asked by sv 7

Since january 1980 the population of the city of brownville has grown according to the mathematical model y=720,500(1.022)^x, where x is the number of years since january 1980.

explain what the numbers 720,500 and 1.022 represent in the model.

If this trend continues, use the model to predict the year during which the population of brownville will reach 1,548,800.

2007-12-30 17:31:38 · 5 answers · asked by Lovelygirl 1

What velocity does the ball hit the grond?

gravity=-32ft/sec.sq

2007-12-30 17:19:22 · 4 answers · asked by Anonymous

If an event is post on the same day like for an example a math competition and a sports day with the students at your school which one would you go to and why? I want to go to both, but now its on the same day and same time, so I need your vote? Which one would YOU rather go to the sports day thingy, or the math competiton, I want to go to both but I can't cast your vote with a reason PLEASE!!!!

2007-12-30 17:04:47 · 7 answers · asked by Anonymous

(x+3)/(x-1)

2007-12-30 17:03:05 · 8 answers · asked by ashlea o 2

How many sec. will the ball be going up?

gravity =-32ft/sec.sq

2007-12-30 16:56:53 · 4 answers · asked by Anonymous

2007-12-30 16:44:50 · 10 answers · asked by MARIE D P 1