Answer:
a) half life is 3h 17 minutes
b) function of residue drug after t hours with initial quantity = 500 mg
f(t) = 500 (0.81^t)
c) drug left in patient's system after 24 hours
= 0.00 grams (to the hundredth of a gram.
Step-by-step explanation:
Given:
Drug initial active weight, A = 500 mg
Residue active weight, f(t) = A 0.81^t
t = time in hours.
a) half life
Half life is T, such that f(T) = 0.5A =>
0.5A = A(0.81^t)
0.81^t = 0.5
t*log(0.81) = log(0.5)
t = log(0.5) / log(0.81) = -0.6931 / -0.2107 = 3.2894 hours
= 3 h 17.36 minutes
b) Equation of function of residue drug as a function of time t in hours
A=500 mg
f(t) = A(0.81^t) substitute A = 500 mg
= 500(0.81^t) mg
c) weight of residue drug after 24 hours to the hundredth of a gram.
t=24 hours
A=500
f(t) = 500(0.81^t) substitute t=24 hours
= 500(0.81^24)
= 3.181 mg
= 0.003181 g