can't understand derviatives from searching all over the internet I have tried to follow a lot of tutorials out there for explaining derviatives and show (understandable)examples but i couldn't understand any. Can anyone link me a useful and easy to follow tutorial or explain derviatives  for me?

Let me give you a very simple one. 
lets say you want to find out the derivative of
 $$3x^2$$
You bring down the exponent which is 2 and multiply it by 3, just like this. 
2*3x 
and then you subtract that exponent by 1. 
so it should look like this: $n*(3x^{n-1})$
therefore the answer would be 6x. There's other rules and etc, however this is just a basic idea and concept of it. 
