# Math Help - differentiation basics

1. ## differentiation basics

I have some problems with these differentiation questions. I've not done maths in a while and am revising currently. The question is

use the differentiation of the derivative to find f '(x) when f(x) is given by

(a) 1/x+1 and (b) 3/x^2

2. *** that was supposed to say definition of derivative :P

3. Originally Posted by scott.b89
I have some problems with these differentiation questions. I've not done maths in a while and am revising currently. The question is

use the differentiation of the derivative to find f '(x) when f(x) is given by

(a) 1/x+1 and (b) 3/x^2

(a)
f (x)
=1/x+1
=(x+1)^-1
f '(x)
=(-1) [(x+1)^-2] (1)
= -1/[(x+1)^2]

(b)
f(x)
=3/x^2
=3x^(-2)
f '(x)
= -6x^-3
= -6/(x^3)

4. ## cheers

clearly a little rusty :P