Acircular plate is being heated. its radius is increasing at the rate of 0.02 in/min. at what rate is the area of the plate increasing at the instant when the radius is 6 inches.

Step-by-step explanation:

Data given

r = 6 in

Solution to the problem

We know that the area for a circle is given by:

We want to find at what rate is the area of the plate increasing at the instant when the radius is 6 inches. So we need to take partial derivates in both sides of the equation for the area, and if we do this we got:

Since we have all the values provided we just need to replace and we got:

1/800 is the right answer