Given:

where, f(x) is the amount of a 12-mg dose of antibiotic left in her bloodstream after x hours.
To find:
The remaining mg in her bloodstream after 2 hours.
Solution:
The amount of a 12-mg dose of antibiotic left in her bloodstream after x hours is represented by the function

Putting x=2, we get the remaining mg in her bloodstream after 2 hours.



Therefore, the remaining mg in her bloodstream after 2 hours is 8.0688 mg.