Related Rates, 01As the radius slides through equal intervals of width 0.35, notice that the increases in the area of the circle do not remain constant. That is, an increase of 0.05 in radius makes a greater difference in area when the radius is 0.4 than when it is 0.2 Notice that this change in rate reflects the change in the slope of the function, so that it can be found by looking at the derivative, f ' (x). Dave Matthews, Created with GeoGebra |