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In this video, we're going to go through the answer to question number 25 from chapter 5 .8, where we're asked about a new drug, where the plasma drug concentration is modeled by the function c.
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And in part a, we're asked to find the maximum drug concentration and when it occurred.
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So this is an optimization problem where we're trying to find the maximum or minimum of this function.
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So we need to find the derivative of this function and find out where the derivative is equal to 0.
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So to find the derivative, we can use the product rule.
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We've got e to the minus 2t plus t times the derivative of e to the minus 2t, which is minus 2, each to minus 2 t.
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That's equals 23, each to the minus 2t, 1 minus 2t.
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So this is equal to zero when 1 minus 2t is equal to 0, because e to the minus 2t can never be 0.
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This occurs when t is equal to a half hours.
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And then to find what the maximum concentration is, we need to evaluate the function c at a half.
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So that's 23 times a half times e to the minus 1.
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And this is approximately equal to 4 .23 micrograms per milliliter.
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And that's the answer to question.
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It's to part a...