Derivatives of terms in square roots.

[scrum]

I really hate to keep posting over and over because it's probably annoying but this class is really difficult and I'm having trouble with the weird problems.

How do I find the derivative of



x / (1+2x)

and also

1 / root(x+4)


the way I've been doing it is to use the power rule (ex) 5x^2 + 2x would go to 10X+2
or plug into
lim h->0 (f(x+h)-f(x))/h and go from there, but the fractions and the roots don't go well with those and i don't know the algebra to get them out.(or if that is the right way to approach it)

a poke in the right direction would be appreciated.

 

[royhaas]

You can still use the power rule, for example the first function can be written as \(\displaystyle (1/2)(1-1/(1+2x))\).

 

[scrum]

thanks. Our teacher told us this today.

my homework is ridiculous, I had to learn the chain rule from the internet to do half my homework.