# What does this notation mean? Leibniz's notation for second derivative?

• Mar 9th 2011, 09:29 PM
Tim92
What does this notation mean? Leibniz's notation for second derivative?
Hi everyone,

I have come across the following notation and I'm not sure what it means:
Attachment 21093

I thought it meant the second derivative but I have only ever seen that denoted:
Attachment 21094

Can anyone help me out here?

Thanks, Tim.
• Mar 10th 2011, 02:23 AM
HallsofIvy
It doesn't mean anything. It is probably a misprint for the second derivativel,
$\frac{d^2y}{dx^2}$

The other possibility is that it is a misprint for
$\frac{dy^2}{dx}= 2y\frac{dy}{dx}$.