1. ## differentiating

Hello, I am trying to understand how this was differentiated:
1/3x^3

I would have thought:
-3x^-3
9x^-4
9/x^4

but I know this wrong.
Can someone please point out where I am going wrong ?

Thanks kindly.

2. Originally Posted by fran1942
Hello, I am trying to understand how this was differentiated:
1/3x^3

I would have thought:
-3x^-3
9x^-4
9/x^4

but I know this wrong.
Can someone please point out where I am going wrong ?

Thanks kindly.
Is it 1/(3x^3) ??

Then it's (1/3)x^-3, the derivative is
-3(1/3)x^-4 = -1x^-4 = -1/x^4

3. Originally Posted by fran1942
Hello, I am trying to understand how this was differentiated:
1/3x^3

I would have thought:
-3x^-3
This is your mistake. $1/3= 3^{-1}$, not $-3$
9x^-4
9/x^4

but I know this wrong.
Can someone please point out where I am going wrong ?

Thanks kindly.[/QUOTE]