Question

caculate the derivatives using by difination:
f(x)= ln x

Answer 1

the derivative of lnx is (1/x)

Answer 2

how?

Answer 3

truth be told i really dont know...its just one of those diff. rules i was taught and was told to memorize.

though if you really want to know why i guess you can watch this video for the proof.

http://www.khanacademy.org/video/proofs-of-derivatives-of-ln-x--and-e-x?playlist=Calculus

Answer 4

thanks I need to proof it.

Answer 5

no problem :)