4 micrograms of a drug is administered to a patient. The amount of drug left in the blood after a certain period if time is given by the formula: A=4*(0.87)^t where t is the time(hours) and A is the amount of drug left. Algebraically determine how many hours after the drug has been administered that the amount of drug in the blood in the blood is halved.

Question

4 micrograms of a drug is administered to a patient. The amount of drug left in the blood after a certain period if time is given by the formula: A=4*(0.87)^t  where t is the time(hours) and A is the amount of drug left. Algebraically determine how many hours after the drug has been administered that the amount of drug in the blood in the blood is halved.

anonymous · Answer

you'll have to solve this equation:
2 = 4*(0.87)^t

anonymous · Answer

1/2=(0.87)^t
ln(1/2) = t*ln(0.87)

anonymous · Answer

sorry, but what is the "In" in the last equation?