# Math Help

1. Jun 6, 2005

2. Jun 6, 2005

### whozum

Please try not to double post, it can be confusing for those helping you.

3. Jun 6, 2005

### eutopia

sorry... i posted in physics and didnt realize it... and i didnt know how to move it

4. Jun 7, 2005

### hen

books

if you know hebrew, he IS THE GURU... (many good ppl in the hebrew univ' learned from it)
David Maizler, "Heshbon Infinitesimali"
English:
Morris Kline's "Calculus, An Intuitive & Physical Approach". ISBN: 0-486-40453-6
rigorous text, not an intuitive one:
Spivak, CALCULUS Courant & John, INTRODUCTION TO CALCULUS AND ANALYSIS Apostol, CALCULUS

5. Jun 7, 2005

### quetzalcoatl9

eh? what are you talking about, this is a basic calculus problem to demonstrate the definition of the derivative.

eutopia, notice that you can write:

$$| 3x - 6 | < \epsilon$$
$$| x - 2 | < \delta$$

What if we multiplied the second inequality by 3?

and be sure to check your book again...i would be surprised if your calculus text did not have a section on the modern definition of the derivative.

6. Jun 7, 2005

### SteveRives

Shalom, ma shlomha?

Let's cheat a little.

You know the slope of the line is 3, right? Since f(x) = 3x + 1, then m = 3.

It is not hard to imagine that "e" and "d" are rise and run. So we could write this: 3 = e/d.

The question is, for every rise, is there a run (for every e, is there a d)? The answer is yes. We know that 3 = e/d, we can solve for d:

d = e / 3.

This is just another way to help you think of the problem. e and d is the slope finding game. I give you an e, you give me a d.

Does the line 3x + 1 have a slope everywhere? Of course.

Now, this method covers the trivial case, but it gives you another way to look at it. Imagine a function besides a line that does not have one single slope, like m = 3, then you start getting into slope functions.

--SR