A bacteria culture initially contains cells and grows at a rate proportional to its size. After an hour the population has increased to . (a) Find an expression for the number of bacteria after
hours.(b) Find the number of bacteria after 3 hours.(c) Find the rate of growth after 3 hours.(d) When will the population reach 10,000?

Respuesta :

Answer:

Step-by-step explanation:

given that a  bacteria culture initially contains cells and grows at a rate proportional to its size.

If P be the size then growth rate

[tex]P'=kP[/tex] where k is constant of proportionality

separate the variables as

[tex]\frac{dP}{P} =kdt\\ln P =kt+C\\P = Ae^{kt}[/tex]

If after 1 hour population is B (say)

[tex]B=Ae^{k} \\\\k = ln B - ln A[/tex]

then k = ln B - ln A

Using this

P(t) = [tex]Ae^{(lnB-lnA)t}[/tex]

b) P(e) = [tex]Ae^{(lnB-lnA)3}[/tex]

c) Rate of growth = [tex](ln B- ln A)Ae^{(lnB-lnA)3}[/tex]

Unless you give B value, d cannot be solved