Mathematics - 11 November 2007

2007-11-11 22:33:06 · 2 answers · asked by Drey 2

why is 1/i = -i, I don't understand how it's -i

can someone explain to me why 1/i = -i

thanks

2007-11-11 21:30:21 · 4 answers · asked by Anonymous

its easy to memorize, the problem with memorization is that it usually stays in your head for about a week or so, and then its gone. I find that if I understand why something is, if I understand the concept, if I am able to visualize it I can remember it for a long time, perhaps forever. I am having trouble visualizing and understanding changes of variables in multivariable calculus, can someone please help me visualize it?

2007-11-11 21:22:57 · 5 answers · asked by Anonymous

2007-11-11 20:23:54 · 6 answers · asked by chelly 1

2007-11-11 19:44:27 · 2 answers · asked by MANDY 1

I can't solve some word problems.

Find four consecutive integers such that the sum of the two greatest subtracter from twice the sum of the two least is 15.

and

The atomic numbers of radium, thorium, and uranium are consecutive even integer in increasing order. If three times the atomic number of radium is 82 more than the sum of the atomic numbers of thorium and uranium, what are the atomic numbers of these three elements?

Please help.

2007-11-11 19:38:27 · 2 answers · asked by Anonymous

A total of 764 tickets were sold for the school play. There were 64 more student tickets sold than adult tickets. How many adult tickets were sold?

2007-11-11 19:30:25 · 5 answers · asked by Ballin! 1

2007-11-11 19:10:38 · 2 answers · asked by Anonymous

http://i40.photobucket.com/albums/e215/xxs3xp1stolxx/Algebra%20II/411q/Picture2.png
6. Name a column matrix.
7. Name a row matrix.
8. What are the dimensions of Matrix S? Make sure you give them in the correct order.
9. What element is in Matrix M, row 3, column 2?
10. a.) If you multiply Matrix S by Matrix T (S times T), what are the dimensions of the new matrix?

b.) If you multiply Matrix T by Matrix S (T times S), what are the dimensions of the new matrix?

c.) Is the answer matrix to part b different than the one in part a? Why?

2007-11-11 18:59:34 · 4 answers · asked by Anonymous

http://i40.photobucket.com/albums/e215/xxs3xp1stolxx/Algebra%20II/411q/Picture1.png
1. -4Q
2. L - 3P
3. RS
4. N - M
5. N + T

2007-11-11 18:55:07 · 2 answers · asked by Anonymous

Show that
(1/2(a+(a^2+b^2)^-2))^-2+i(1/2(-a+(a^2+b^2)^-2))^-2
squares to a+ib.

2007-11-11 18:06:52 · 1 answers · asked by Anonymous

Consider a function f which satisfies the following properties:
(i) f(x+y)= f(x)f(y)
(ii) f(0)≠0
(iii) f(0)=1

1. Use the definition of the derivative to show that f'(x)=f(x) for all real numbers x.

2. Let g be another function that satisfies properties (i)-(iii) and let k(x)=f(x)/g(x). Show that k is defined for all x and find k'(x). Use this to discover the relationship between f and g.

3. Can you think of a function which satisfies (i)-(iii). Can there be more than one such function?

Please help! I don't understand how to approach this problem at all!

2007-11-11 17:57:57 · 2 answers · asked by Jess 2

Can anyone answer this and PLEASE tell me how they got their answer.

Which of the following expressions represents the product of 3 less that twice x and 2 more than the quantity of 3 times x?

A. -6x squared + 25x +6
B. 6x squared + 5x + 6
C. 6x squared + 5x + 6
D. 6x squared - 5x - 6
E. 6x squared - 13x - 6

2007-11-11 17:48:03 · 6 answers · asked by Anonymous

Please list starting from Geometry in 9th grade.

2007-11-11 17:23:24 · 9 answers · asked by nerris121 4

2007-11-11 17:21:31 · 4 answers · asked by Anonymous

solve using augmented matrices:
x + 2y - z = 3
3x + y - 2z = -6
x + y + z = 1

i've been trying to do this for almost twenty minutes and i'm dying :[
someone please help, and show your work? teehee

2007-11-11 17:20:16 · 1 answers · asked by winniemazing 2

2cosx-3tanx=0

My previous exercise asked Sinx-2Sin^2x=0, which I could do fine-- But I don't understand this one. If someone can help, I'd appreciate it!

2007-11-11 17:10:25 · 1 answers · asked by William F 1

when 10 123 456 789 876 543 210 is divided by 55.... i have a feeling that i need to use the chinese remainder theorem, but im not 100% sure... please please please show your method, seing as how i already know the correct answer...

2007-11-11 17:01:38 · 1 answers · asked by Anonymous

3x^2 - 2x = 0

Thank you.

2007-11-11 16:49:13 · 9 answers · asked by Anonymous

At 9:00 a.m. a truck leaves the truck yard and travels west at a rate of 35 mi/hr. Two hours later, a second truck leaves along the same route, travelling at 70 mi/hr. When will the second truck catch up to the first?

2007-11-11 16:48:04 · 3 answers · asked by christatsotaddle 2

2007-11-11 16:45:04 · 12 answers · asked by j_fraz07 1

Please explain how to do this simultaneous equation (the steps involved), I know the answer, i just need to know how to do it.

y=4x-3
y=4-3x

ya ya i know it looks simple and it probably is :p

2007-11-11 16:43:48 · 3 answers · asked by Anonymous

Does sqrt(a^2 - b^2) = a - b ?
If so or not, why ?

2007-11-11 16:38:58 · 5 answers · asked by c0cky 5

A company manufacturing lawn-mowers
finds that its weekly cost and demand equations are

C(x) = 80 + 24x; p(x) = 60 - x/6

when it sells x lawn-mowers per week. If
the company can sell all the lawn-mowers it
manufactures, determine the maximum profit
from the sale of these lawn-mowers.

1. maximum profit = $1854
2. maximum profit = $1864
3. maximum profit = $1859
4. maximum profit = $1874
5. maximum profit = $1869

2007-11-11 16:34:33 · 1 answers · asked by Damian 1

The populatin p(t) of a certain group of rabbits satisfies the initial value problem:
dp/dt = kp^2 , p(0) = p(not)
where k is a positive constant, derive this solution

The answer is (p) = p(not) /( 1 - kp(not)t)
Can someone explain how I can get to the final equation

2007-11-11 16:11:04 · 3 answers · asked by Anonymous

1 mm is equal to how many meters?

2007-11-11 16:09:46 · 6 answers · asked by Eun Chul M 1

Suppose that A ⊂ B show that complement of B ⊂ complement of A ?

if you have answers to Probability and statistics by Morris H.Degroot and Mark J. Schervish in PDF or anykind

please email me the file.

thank you

2007-11-11 16:01:13 · 1 answers · asked by Anonymous

Hi I was absent Thursday for school because I had to go to the clinic to get my shots but when i went back to school Friday form my 3/4 Double Period Algebra my teacher passed me a Worksheet that she handed in Thursday but I don't know how to do it I asked my friends if they could help but they were bogus and said no so plzz yahoo answers I need your help I would really appreciate it

Winner gets 5 Stars 10 points!!!!!



In Exercises 1-18, choose from the box at the right the algebraic expression that represents each word expression. More than one answer may be positive in some cases.

1. The Product of y and (-6)
2. y minus 6
3. 6 plus y
4. y increased by 6
5. Subtract 6 from y
6. The quotient of y and (-6)
7. Six Times y
8. y more than 6
9. Subtract y from 6
10. 6 less y
11. 6 less than y
12. The product of (-6) and y
13. The quotient of (-6) and y
14. -6 multiplied by y
15. y divided by (-6)
16. The Sum of 6 and y
17. 6 divided by (-6)
18. 6 diminished by y

2007-11-11 15:58:49 · 7 answers · asked by Anonymous

solve for all the zero's showing all work

2007-11-11 15:57:58 · 3 answers · asked by Anonymous

2007-11-11 15:37:19 · 1 answers · asked by !z@@h. (はりざ ) 4