calculus
posted by mandy on .
A potter forms a piece of clay into a cylinder. As he rolls it, the length,L, of the cylinder increases and the radius, r, decreases. If the length of the cylinder is increasing at .1 cm per second, find the rate at which the radius is changing when the radius is 1 cm. and the length is 5 cm.

Volume is remaining the same. Think on that.
V=PI*r^2 * L
dv/dt= 2PI*L r dr/dt+ PI*r^2 dL/dt=0
solve for dr/dt 
.001