Math function problem: F(t)= 90-521n(1+t), 0 <t<4?

Question

I'm trying to review functions but i don't know how to do this one.

The questions asks what is the initial number of units of drug administered? How much is present after two hours?

Problem says: The function t gives the number of units of the drug in the body after t hours.

How do i go about solving this?

Answer 1

F(t) = 90 - 52 ln(1 + t)

ln is the &quot;natural log&quot; (base e where e ≈ 2.71828)

The initial number of units administered is F(0).

F(0) = 90 - 52 ln(1) = 90 - (52)(0) = 90

The amount present after 2 hours is F(2).

F(2) = 90 - 52 ln(3) ≈ 90 - (52)(1.0986) = 32.8728