## Search found 8 matches

Mon Nov 30, 2009 8:04 am UTC
Forum: Mathematics
Topic: Need help constructing a general solution
Replies: 2
Views: 607

### Re: Need help finding construcing a general solution

PM 2Ring wrote:You're very close. Have you studied Mathematical Induction yet?

BTW, you need to use braces to group stuff for LaTeX, like this:
$S_n = S_{n-1} + S_{n-1}*i$

Yes I have and thank you. I wondered whether i might have to do it by induction. I will let you know how it goes.

Thank you once again.
Mon Nov 30, 2009 5:59 am UTC
Forum: Mathematics
Topic: Need help constructing a general solution
Replies: 2
Views: 607

### Need help constructing a general solution

Hi xkcd I've been trying to tackle a problem given to me. The problem is as follows: The initial amount in a savings account is \$1000. Each month, 1% of the total amount in the account is added to the total amount. So I decided to call amount saved S and i is the interest rate. Hence the intial amou...
Sun May 10, 2009 5:03 pm UTC
Forum: Science
Topic: Name for the phenomenom where liquid "creeps" up the side...
Replies: 5
Views: 1052

### Re: Name for the phenomenom where liquid "creeps" up the side...

Ended wrote:Meniscus?

This is it. Thanks very much to everyone that posted!
Sun May 10, 2009 3:37 pm UTC
Forum: Science
Topic: Name for the phenomenom where liquid "creeps" up the side...
Replies: 5
Views: 1052

### Name for the phenomenom where liquid "creeps" up the side...

...of a container.

What i mean is, what is it called when this happens: Wed Jan 28, 2009 12:02 am UTC
Forum: Mathematics
Topic: Cumulative Distribution Function question
Replies: 2
Views: 502

### Re: Cumulative Distribution Function question

As you noted, the CDF is just the integral of the density function. First, as you did, find F(1): F(1) = \int_0^1 \frac 3 8 t^2 dt = \left. \frac 1 8 t^3 \right|_0^1 = \frac 1 8 Then, on the interval [1,3], F(t) is given by F(t) = F(1) + \int_1^t \frac{s+5}{16} ds = \frac 1 ...
Tue Jan 27, 2009 11:21 pm UTC
Forum: Mathematics
Topic: Cumulative Distribution Function question
Replies: 2
Views: 502

### Cumulative Distribution Function question

Doing a past exam paper, I came across the following question. This is the Probability Density Function: f(t) = (3/8) t^2, 0 <= t < 1 f(t) = (1/16) (t+5), 1<= t <= 3 0 otherwise I am asked to show that the cumulative distribution function for 1<=t<=3 is given ...
Thu Oct 09, 2008 10:44 pm UTC
Forum: Mathematics
Topic: Need help proving a trigometric identity
Replies: 11
Views: 2789

### Re: Trigometric proving problem

Well, the first thing I notice is sec 2 A-tan 2 A. Does that simplify to anything? Yes. It simplifies to 1, but I don't see where to go from there. cos^2(x)+sin^2(x)=1 perhaps? For questions like this it's almost always best to write everything out in terms of cos and sin, IMO. It makes spotting id...
Thu Oct 09, 2008 9:26 pm UTC
Forum: Mathematics
Topic: Need help proving a trigometric identity
Replies: 11
Views: 2789

### Need help proving a trigometric identity

Hi, I was working through some questions in my textbook when i came across this one which i can't quite prove. The question is as follows: Prove that: (secA-tanA)(secA+tanA) / cosecA-cotA = cotA+cosecA So far I have got as far as: sec^2(A)-tan^2(A)/cosecA-cotA Could someone please point me in the ri...