Register to reply

Volume of a cube versus side length

by emma3001
Tags: cube, length, versus, volume
Share this thread:
emma3001
#1
Apr14-08, 06:38 PM
P: 42
Show that the rate of change of the volume of a cube with respect to its edge length is equal to half the surface area of a cube.

I know that surface area= 6l^2(because of the six faces)
I know that volume is l^3. How do I relate volume then to edge length
Phys.Org News Partner Science news on Phys.org
Experts defend operational earthquake forecasting, counter critiques
EU urged to convert TV frequencies to mobile broadband
Sierra Nevada freshwater runoff could drop 26 percent by 2100
Pere Callahan
#2
Apr14-08, 07:19 PM
P: 587
Quote Quote by emma3001 View Post
Show that the rate of change of the volume of a cube with respect to its edge length is equal to half the surface area of a cube.

The "rate of change" is the derivative.

So what is the derivative of the volume with respect to the edge length?
emma3001
#3
Apr14-08, 07:21 PM
P: 42
Thanks! I now realize that the first derivative of the volume is 3l^2, which is half the surface area

Pere Callahan
#4
Apr14-08, 07:24 PM
P: 587
Volume of a cube versus side length

Right.


Register to reply

Related Discussions
Hieght of a volume in a cylinder on its side, with known volume. Precalculus Mathematics Homework 2
Cube volume Precalculus Mathematics Homework 2
A simple problem that's dirving me crazy (Perimeter and length of each side) Precalculus Mathematics Homework 5
Volume of a cube General Math 3
In 1998 Hubble volume meant a cube 12 billion LY on a side General Physics 10