# Homework Help: Math Question

1. Apr 10, 2007

### darthchocobo

Ok. K this equation I am suppose to make has to variables
The magnitude is increasing at a certain rate. It is a pattern. I need to find an equation for this pattern

Say we have:

r^0
r^1
r^3
r^6
r^10

Ok. As you can see, the added magnitude is increasing by 1 everytime. I need to create this equation where the magnitude is a variable. So it could be like r^n+1 or something like that. Lol. Plz help asap.

2. Apr 10, 2007

### symbolipoint

The exponents fit the form, $$\sum _1 \^{n} \(n-1)$$

[in case the typesetting did not work, I said, summation from 1 to n, of (n-1)]

3. Apr 10, 2007

### symbolipoint

.....in fact, the typesetting did NOT work; I will try studying other messages for anything doing what I tried.

Let me try again now:

$$\sum_1^n \((n-1)$$ If that does not work, then check my description in previous message.

Last edited: Apr 10, 2007
4. Apr 11, 2007

### symbolipoint

This also might not work well because I'm still trying to learn the typesetting, but any k term would be :

$${r}^{\frac{k(k-1)}{2}$$
... or in simple text form,
r^(k(k-1)/2)

Check an intermediate algebra book for how the expression formula was developed.

5. Apr 11, 2007

### HallsofIvy

The "tutorial" section is for just that- tutorials showing people how to do things. Questions should be posted in the "Homework" section. I am moving this thread to that section.

Your exponents are "triangular" numbers: n(n+1)/2. The form you want is just what symbolipoint said in his last post.