Posted by justin on .
The concentration C (in milligrams per milliliter) of a drug in a patient's bloodstream t hours after injection into muscle tissue is modeled by
C =
3t/26 + t^3
Use differentials to approximate the change in the concentration when t changes from
t = 1
to
t = 1.5.
(Round your answer to four decimal places.)

math calculus 
Steve,
C = 3t/26 + t^3
dC = (3/26 + 3t^2) dt
Just plug in t=1, dt=0.5