How do you differentiate this function?
$$f(x)=\tan^{-1}\left(\frac {12x-64x^3}{1-48x^2}\right)$$
I tried to change what's inside the inverse tan function to get the identity of the sum or difference between two angles but I can't get it right.
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1Do you know about chain rule when differentiating? – Bermudes Mar 03 '19 at 20:43
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yes i know the chain rule but I want a quick way to approach the solution – John C. Mar 03 '19 at 20:44
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It's a triple-angle rule: if $\tan\theta=4x$, $\tan 3\theta = \frac{3\cdot 4x-(4x)^3}{1-3\cdot (4x)^2}$. I'll leave it to you from there.
jmerry
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