Question

can someone PLEASE tell me what the derivative of:
x(12-2x)^2 is?????

Answer 1

You can use the product rule to differentiate it; or expand it out.
Have you tried it?

Answer 2

the easiest way to do this is to simply expand, and do each part seperately

Answer 3

x(144+4x^2-48x) = 144x + 4x^3 - 48x^2

Derivative:
144 + 12x^2 - 96x

Answer 4

I have tried everything. I think the answer in the book is wrong but I wanted to make sure.

Answer 5

GT HOW did you get that???

Answer 6

You understand how I got this one, right?
144x + 4x^3 - 48x^2

Now, derivative of that is:
d/dx 144x = 144
d/dx 4x^3 = 4*3*x^2
d/dx -48x^2 = -48*2*x

Answer 7

I think I had that before but I erased it.

Answer 8

So, finally, you get:
144 + 12x^2 - 96x

Answer 9

Yes thank you!!!! At first I thought I had to use the chain rule but I guess I was over thinking it.

Answer 10

Well....you could. But, this one is simple enough to expand out.

Answer 11

I wasn't getting it with the chain rule. It's been about 15 years since I have had calculus. I'm rusty! Thanks though!

Answer 12

No worries.

Answer 13

No, GT. Chain rule is for the composition of two functions f(g(x)). Product rule is for the product of two functions f(x)*g(x).

Answer 14

Sorry.....confused the two. yeah...I meant product rule. :)

Answer 15

:)

Answer 16

There....removed the error.