Derivative of (x+3)(x-4)(x+5): A Simple Guide

[sbose27]

Sorry for not using JavaScript or whatever script is needed, I don't have enough time to figure it out b/c my class is soon... anyways I just need to know know to find the derivative of 3 groups of parentheses

(x+3)(x-4)(x+5)

I've tried using the product rule on the first two and then using the rule on the result from that and (x+5) but it's not working. I'm an idiot.. thanks for any help.

 

[neutrino]

It's a simple extension of the product rule: (uvw)' = u'vw + uv'w + uvw', where u,v and w are functions of x.

 

[sbose27]

It's a simple extension of the product rule: (uvw)' = u'vw + uv'w + uvw', where u,v and w are functions of x.

okay thanks a lot

 

[end3r7]

I've tried using the product rule on the first two and then using the rule on the result from that and (x+5) but it's not working.

That should work actually.
If you call the 3 functions u(x), v(x) and w(x) and let y(x) = u(x)v(x), then [y(x)w(x)]' = y'w + yw'. Just replace y = uv and y' = u'v + uv', you get (u'v + uv')w + uvw' = u'vw + uv'w + uvw', which is exactly what neutrino.