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This is problem number 52 of the stewart calculus 8th edition, section 2 .8.
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The figure shows the graphs of four functions.
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One is the position function of a car.
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One is the velocity of the car.
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One is its acceleration.
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And one is its jerk.
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Identify each curve and explain your choices.
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So here we have our graph where it shows all four curves, a, b, c, and d.
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And we're just going to start, let's say, with curve d and see what we can determine.
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From discussing the derivative of each function.
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So if we look at curve d, it is always increasing.
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If this curve is always increasing, its derivative must only be above the x -axis, so only positive.
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And we see that this is only true of graph c.
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This curve a and b, they have negative parts, meaning that there's no way that a curve a and curb b can describe the ever -increasing derivative of d, the ever -increasing nature, behavior of d.
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So curb c must be the derivative of curve d.
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Curve c itself is all increasing up until it gets to this point here, where it maxes out, small minimum, maximum.
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Afterward, it just slightly decreases...