Question

For a dosage of x cubic centimeters (cc) of a certain drug, the resulting blood pressure B is approximated by the function below. Find the maximum blood pressure and the disage at which it occurs.

B(x)= 395x^2- 2370x^3, 0 <= x <= 0.16

a. The maximum is obtained for a dosage of __________________.
b. The maximum blood pressure obtained is ______________.

Answer 1

A) Maximum for dosage is 0.11

B) maximum blood pressure = 1.625

Explanation:

We are given the function;

B(x) = 395x² - 2370x³

To find maximum, we will find the derivative of the function and equate to zero.

B'(x) = 790x - 7110x²

Equating to zero gives;

790x - 7110x² = 0

790x = 7110x²

Dividing both sides by x gives;

790 = 7110x

x = 790/7110

x = 0.11

This falls in between the range of 0 <= x <= 0.16 given to us.

Therefore x = 0.11 is a maximum

Plugging this into B(x) = 395x² - 2370x³ gives;

B(0.11) = 395(0.11)² - 2370(0.11)³

B(0.11) = 1.625

Thus;

Maximum dosage is 0.11

maximum blood pressure = 1.625