What is the derivative of 3x(8-x)^3

Question

anonymous · Answer

product rule

anonymous · Answer

I tried the product rule and got this ridiculous thing: 9x + 3(x-8)^5 ... I probably did it incorrectly, as I'm supposed to figure out which x's make it equal to zero to find mins and maxes.

anonymous · Answer

With the chain rule, I got (72 - 9x)^2 ... Sounds more reasonable, but I'm still new to derivatives, so I was hoping for a bit of help. ><;

anonymous · Answer

Is it easier to take the derivative of the following expression?
$$1536 x-576 x^2+72 x^3-3 x^4 $$

abb0t · Answer

easy for you, but not easy for everyone else.

zzr0ck3r · Answer

how can it get any easier than a bunch of power rules?

anonymous · Answer

It would be 1,536 - 1152x + 216x^2 - 12x^3 ? Maybe? xD

zzr0ck3r · Answer

correct

abb0t · Answer

i DON'T UNDERstand any Of ThIs!!

anonymous · Answer

Is my answer via product rule correct, though?

zzr0ck3r · Answer

ahh yes

anonymous · Answer

It just seems so re-donkey-lips to try putting the f' equal to 0 when set up that way and finding x. But I suppose I must. Thankya for the help.