"Let a,b be in R with a>0 and f(x)=ax^3+bx. Let k(x)=[f''(x)]/[1+(f'(x))^2]^(3/2). Find the critical points of k(x) and use the first derivative test to classify them."(adsbygoogle = window.adsbygoogle || []).push({});

This seems incredibly quantitative and complicated for an analysis assignment. There must be a theorem of some kind I can use to solve this, but I can't see it.

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# Homework Help: Critical Points

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