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## #1 Help Me ! » volume of a cone » 2006-11-21 13:09:23

Joel
Replies: 10

Can anyone help me, how to derive the formula of the volume of the cone 1/3*pi*r^2*h ?

## #2 Re: Help Me ! » Discrete maths - characteristic functions » 2006-11-10 13:29:54

Let A={ a,b,c,d......x,y,z}
Let B={ a,e,i,o,u}

Characteristic function is defined as

I(x) = { 1, if x belongs to B,
= { 0, if x doesnot belong to B.      where x is a variable, which can take any letter from the alphabets.

For ex:
If the letter is 'a', then the value is  0.
If the letter is 'e', then the value is  1.

I have given what i know. If u find any mistake, pls correct me.

## #3 Re: Help Me ! » Help me....Limits without using 'L' Hospital's rule » 2006-11-09 10:28:18

Good question. Keep posting such types of questions. Let me also try this. Hope to get the answer soon. All the best.

## #4 Re: Help Me ! » speed and distance » 2006-11-09 09:32:57

The train traveled at s meters per minute for d meters and arrived t minutes late to its destination. How fast should the train have traveled to make it to its destination on time?

## #5 Help Me ! » speed and distance » 2006-11-09 09:27:56

Joel
Replies: 3

The train traveled at s meters per minute for d meters and arrived t minutes late to its destination. How fast should the train have traveled to make it to its destination on time?