Originally Posted by

**bpdude** I need some assistance on several problems I am absolutely stuck on:

1.

"The quantity of a drug, Q mg, present in the body t hours after the injection of the drug is given is:

Q=f(t)=80t** * **e^-0.38t

find:

f(1)= **54.71**

f'(1)=______

f(6)=**49.10**

f'(6)=______

Round your answers to two decimal places."

I know I'd find the derivative of f(t). Would it be:

80t(-.38t)e^-.38t **<<<<<<< No. You have to use the product rule here (see above)**

?

2nd question:

"A dose, D, of a drug causes a temperature change, T, in a patient. For C a positive constant, C=32, T is given by:

T=((C/2)-(D/3))D^3

What is the rate of change of temperature change with respect to dose?

dT/dD=_____

For what doses does the temperature change increase as the dose increases?

D < _____"

Not sure where to start here. Maybe substitute C=32 **OK then expand the bracket **and take the derivative of the equation **!**

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