Carlos has taken an initial dose of a prescription medication.The relationship between the elapsed time t, in hours, since he took the first dose, and the amount of medication, M(t), in milligrams ( mg ), in his bloodstream is modeled by the following function.M(t)=20⋅e−0.8tIn how many hours will Carlos have 1mg of medication remaining in his bloodstream?Round your answer, if necessary, to the nearest hundredth.hours
Q. Carlos has taken an initial dose of a prescription medication.The relationship between the elapsed time t, in hours, since he took the first dose, and the amount of medication, M(t), in milligrams ( mg ), in his bloodstream is modeled by the following function.M(t)=20⋅e−0.8tIn how many hours will Carlos have 1mg of medication remaining in his bloodstream?Round your answer, if necessary, to the nearest hundredth.hours
Given function: Write down the given function that models the amount of medication in Carlos's bloodstream over time.M(t)=20⋅e(−0.8t)
Finding remaining medication time: Set the function equal to 1mg to find the time when Carlos will have 1mg of medication remaining in his bloodstream.1=20⋅e(−0.8t)
Isolating the exponential term: Divide both sides of the equation by 20 to isolate the exponential term.201=e(−0.8t)
Simplifying the equation: Simplify the left side of the equation. 0.05=e(−0.8t)
Taking the natural logarithm: Take the natural logarithm (ln) of both sides to solve for t.ln(0.05)=ln(e−0.8t)
Simplifying the right side: Use the property of logarithms that ln(ex)=x to simplify the right side of the equation.ln(0.05)=−0.8t
Solving for t: Divide both sides by −0.8 to solve for t.t=−0.8ln(0.05)
Calculating the value of t: Calculate the value of t using a calculator.t≈−0.8ln(0.05)t≈−0.8−2.9957t≈3.744625
Rounding the answer: Round the answer to the nearest hundredth. t≈3.74 hours
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