We first write everything in mathematical notation:
Now we may use the Chain Rule, remembering that , , and are all functions of .
This confused me a little bit:
Suppose that side a is increasing at a rate of 1.5 meters/second and c is fixed at 8 meters.
i) Find the rate of change of the measure of angle A when b=4 meters.
ii) Find the rate of change of the measure of angle B when b=4 meters.