# Vector calculus

1. Sep 8, 2005

### Giuseppe

Hello, I just learned how to do these types of problems, but I'm having trouble. Can some one direct me through this problem?

Find the point or points on the curve which the curvature is a maximum for

a. y=ex
b. xy=1

any help is greatly appreciated. I really am stuck here!

2. Sep 8, 2005

### amcavoy

Is that ex or ex?

Do you know the formula for curvature? If so, find the curvature of each, then optimize it! If not, then that is what you should look up first

By the way, like I have mentioned a few times here:

$$\kappa=\frac{|\mathbf{r}'\times\mathbf{r}''|}{|\mathbf{r}'|^3}$$

You can use r = (x)i + (ex)j for the first, and the second is similar (I think you can see what it will be).

Last edited: Sep 8, 2005
3. Sep 8, 2005

### Giuseppe

ah , i think i got it. thanks, i was being stupid