Question

A colony that initially has 70 bacteria triples every day.

Write a natural growth model to express the number of bacteria in the colony as a function of time in days.

Answer 1

A{0} = 70; A{n} = 3(A{n-1}) is our difference equation

Answer 2

A{1} = 3(70)
A{2} = 3(3(70))
A{3} = 3(3(3(70))) = 3^3 (70)
A{4} = 3^4 (70)

A{n} = 3^n (70); should do it

Answer 3

this is what I found on this matter (don't remember any more... ):
http://en.wikipedia.org/wiki/Exponential_growth

Answer 4

Thank You

Answer 5

yep