Asked by Anonymous
The shape of a colony of bacteria on a Petri dish is circular. Find the approximate increase in its area if its radius increases from 40 mm to 49 mm.
The estimated change in area is nothing mm2.
The estimated change in area is nothing mm2.
Answers
Answered by
oobleck
A = πr^2
∆A ≈ dr ∆r = 2π*40*(49-40) = 720π
actual change is π(49^2 - 40^2) = 801π
not very close, since ∆r is so big.
∆A ≈ dr ∆r = 2π*40*(49-40) = 720π
actual change is π(49^2 - 40^2) = 801π
not very close, since ∆r is so big.