# Leibniz notation.

• Apr 8th 2010, 08:19 PM
integral
Leibniz notation.
How do you use this notation?

If I have
$\displaystyle f(x)=x^3+5x^2+4$

How do you wright this?
• Apr 8th 2010, 08:31 PM
dwsmith
How do you write in Leibniz?

$\displaystyle \frac{dy}{dx}$ that means you have to take the derivative though.
• Apr 9th 2010, 03:27 AM
integral
Yes, but how do I use it in terms of the equation?

$\displaystyle \frac{dy}{dx}x^3+5x^2+4$

and if I have the notation:

$\displaystyle \frac{d}{dx}$ Or $\displaystyle \frac{d}{dy}$ what does this mean?

?
• Apr 9th 2010, 03:51 AM
coolxal
Since $\displaystyle f(x)=x^3+5x^2+4$, just make y = f(x) so y = $\displaystyle x^3+5x^2+4$.

dy/dx = f'(x).

dy/dx means derivative of y with respect to x.

d/dx is the derivative with respect to x. If you have $\displaystyle \frac{d}{dx}x^3+5x^2+4$ then you just take the derivative of that.

• Apr 9th 2010, 04:20 AM
CaptainBlack
Quote:

Originally Posted by integral
How do you use this notation?

If I have
$\displaystyle f(x)=x^3+5x^2+4$

How do you wright this?

$\displaystyle \frac{df}{dx}=\frac{d}{dx}(x^3+5x^2+4)=\frac{d}{dx }(x^3)+\frac{d}{dx}(5x^2)+\frac{d}{dx}(4)$

etc

CB