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Hi, am I supposed to find the stationary points of the f(x) and g(x) then use the distance formula to solve for the final answer?​

Hi, am I supposed to find the stationary points of the f(x) and g(x) then use the-example-1
User Drawoc
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Answer:

maximum difference is 38 at x = -3

Explanation:

This is nicely solved by a graphing calculator, which can plot the difference between the functions. The attached shows the maximum difference on the given interval is 38 at x = -3.

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Ordinarily, the distance between curves is measured vertically. Here that means you're interested in finding the stationary points of the difference between the functions, along with that difference at the ends of the interval. The maximum difference magnitude is what you're interested in.

h(x) = g(x) -f(x) = (2x³ +5x² -15x) -(x³ +3x² -2) = x³ +2x² -15x +2

Then the derivative is ...

h'(x) = 3x² +4x -15 = (x +3)(3x -5)

This has zeros (stationary points) at x = -3 and x = 5/3. The values of h(x) of concern are those at x=-5, -3, 5/3, 3. These are shown in the attached table.

The maximum difference between f(x) and g(x) is 38 at x = -3.

Hi, am I supposed to find the stationary points of the f(x) and g(x) then use the-example-1
User Sachin Vardhan
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5.5k points