Graphing a cubed root function

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The discussion revolves around graphing the function \(\sqrt[3]{(x^{2}-1)^{2}}\) and calculating its derivatives. The first derivative has been correctly derived as \(\frac{4x}{3\sqrt[3]{x^{2}-1}}\), but there are difficulties with the second derivative necessary for determining concavity. Participants point out potential errors in the second derivative calculation and inquire about the derivative of \(3\sqrt[3]{x^{2}-1}\). Accurate computation of these derivatives is essential for understanding the function's behavior and graphing it effectively.
frosty8688
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1. Graph the following function



2. \sqrt[3]{(x^{2}-1)^{2}}



3. I got the first derivative to be \frac{4x}{3\sqrt[3]{x^{2}-1}} but am having trouble with the second derivative to get the concavity. So far I have \frac{4*3\sqrt[3]{x^{2}-1}-4x*3*\frac{1}{3\sqrt[3]{x^{2}-1}}}{9\sqrt[3]{(x^{2}-1)^{2}}}
 
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frosty8688 said:
1. Graph the following function

2. \sqrt[3]{(x^{2}-1)^{2}}

3. I got the first derivative to be \displaystyle \frac{4x}{3\sqrt[3]{x^{2}-1}} but am having trouble with the second derivative to get the concavity. So far I have \displaystyle \frac{4*3\sqrt[3]{x^{2}-1}-4x*3*\frac{1}{3\sqrt[3]{x^{2}-1}}}{9\sqrt[3]{(x^{2}-1)^{2}}}
There appears to be an error in your second derivative.

What's the derivative of \displaystyle 3\sqrt[3]{x^{2}-1}\ ?
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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