Formula help

[maxboy0801]

Suppose that the population of a certain type of insect in a region near the equator is given by P(t) = 13 in (t+8) where t represents the time in days. Find the rate of change of the population when t = 3

Where could I find this formula to do this problem?

 

[Gene]

They are asking for d(P(t))/dt
Your book should have
d(ln(u)) = du/u
where u = t+8

 

[maxboy0801]

Gene,
Thanks but this is on a leaflet and it isn't described in my text. Would the answer be 1.2 insects?

 

[Gene]

As I said,
d(ln(u)) = du/u so
d(13*ln(t+8)) =
13*d(t+8)/(t+8) =
13*(1/11) =
13/11
It is better to leave it that way but your 1.2 is probably correct except it is insects per day increase.

 

[stapel]

....this is on a leaflet and it isn't described in my text.

You posted this calculus "practice exam" question to the "beginning algebra" category, and say that basic calculus derivatives are nowhere in your text. Are you taking calculus, or elementary algebra?

Thank you.

Eliz.