An IV administers medication to a patient's bloodstream at a rate of 3 cubic centimeters per hour.At the same time, the patient's organs remove the medication from the patient's bloodstream at a rate proportional to the current volume V of medication in the bloodstream.Which equation describes this relationship?Choose 1 answer:(A) dtdV=3k−V(B) dtdV=3−kV(c) dtdV=−3kV(D) dtdV=k−3V
Q. An IV administers medication to a patient's bloodstream at a rate of 3 cubic centimeters per hour.At the same time, the patient's organs remove the medication from the patient's bloodstream at a rate proportional to the current volume V of medication in the bloodstream.Which equation describes this relationship?Choose 1 answer:(A) dtdV=3k−V(B) dtdV=3−kV(c) dtdV=−3kV(D) dtdV=k−3V
Understand the problem: Understand the problem.The IV administers medication at a constant rate of 3 cubic centimeters per hour. At the same time, the patient's organs are removing the medication at a rate proportional to the current volume of medication in the bloodstream. We need to find an equation that represents this situation.
Set up the differential equation: Set up the differential equation.The rate of change of the volume of medication in the bloodstream, dtdV, is equal to the rate of medication being administered minus the rate at which the medication is being removed by the patient's organs.
Translate into mathematical terms: Translate the information into mathematical terms.The rate of administration is a constant 3 cubic centimeters per hour, so this is a positive term in our equation. The rate of removal is proportional to the volume V, which means it will be a negative term since it is being removed. The constant of proportionality is k. Therefore, the equation should have a positive term for administration and a negative term for removal.
Identify the correct equation: Identify the correct equation.Based on the information given, the equation should look like this: (dtdV)=rate of administration−rate of removal. The rate of administration is 3, and the rate of removal is proportional to V, so it should be kV. Therefore, the equation should be (dtdV)=3−kV.
Match with given choices: Match the equation with the given choices.The correct equation from the choices provided that matches our equation from Step 4 is (B) (dtdV=3−kV).
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