circle: a = pi r^2
da/dt = 2pi r dr/dt = 2pi * 10/(pi-1)
square: a = s^2
da/dt = 2s ds/dt = 2*10/(pi-1)
da(circle)/dt - da(square)/dt
= 20/(pi-1) (pi-1) = 20 in^2/s
A circle has a radius lf 10/(pi-1) which is the same value as the side of a square. Both the radius of the circle and the side of the square are gowing at 1 in/sec. Find the difference between the rates of change of their area in in/sec.
1 answer