a measure of the quantity of bacteria in a cubic centimeter of blood of an infected person is modeled by
Q(t) = 80t(.92^t)
t is the time in days since the person became ill. how fast is the quantity changing 7 days after the onset of the illness?

Question

a measure of the quantity of bacteria in a cubic centimeter of blood of an infected person is modeled by
Q(t) = 80t(.92^t)
t is the time in days since the person became ill. how fast is the quantity changing 7 days after the onset of the illness?

jack1 · Answer

if Q(t) = 80t(.92^t)
and t = time
and time = 7days
sub t=7 into
Q(t) = 80t(.92^t)

becomes ====>  Q(7) = 80 x 7 x (.92^7)$$Q(7) = 80 \times 7 \times (.92^7)$$

jack1 · Answer

can u solve from here? @wittless29 ?

anonymous · Answer

that's not what the answer is on the key, I wish it was that straightforward. thanks for trying though

jack1 · Answer

so is the equation i posted above matching ur's in the book/ pdf?

jack1 · Answer

or is it mor like:
$$Q(7) = 80 \times 7 ^{ (0.92^7)}$$?

jack1 · Answer

or something else?