1.

Find the rate of change of the area of a circle with respect to its radius r when (a) r = 3 cm (b) r = 4 cm

Answer»

(a) A = πr2

\(\frac{dA}{dr}\) = π x 2r

= 2π x 3 = 6π cm

(b) A = πr2

\(\frac{dA}{dr}\) = 2πr

= 2π x 4 = 8πcm



Discussion

No Comment Found