I don't post many questions here since I'm usually able to find most of my answers before starting a thread. As only a few of you may know I'm gradually teaching myself calculus. What can I say? I guess I'm that kind of guy.(adsbygoogle = window.adsbygoogle || []).push({});

I've managed to pick up on quite a few good basic ideas. There is one question I have about 'first derivatives'...

The derivative of ( 4x^3 ) is 12x^2. I understand that. How in the heck though does the below example work, in regards to the introduction of the x^2 - x - 2 in brackets?

I'm using 'calculus for dummies' as one source of reading material, besides the entire internet...but can't seem to find out...whats happened. I've missed a beat somewhere.

The function f(x)=3x^4 − 4x^3−12x^2+3 has first derivative

f(x) = 12x^3−12x^2−24x

= 12x (x^2 − x −2)

= 12x (x + 1)(x− 2)

Source - Harvey Mudd College

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# First derivatives question

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