I understand the product rule and how to use it, but I've been told to prove it, and I don't really know how. Could I be helped with this?

Thank you

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- Apr 23rd 2010, 02:52 PMiPodProof of the Product Rule
I understand the product rule and how to use it, but I've been told to prove it, and I don't really know how. Could I be helped with this?

Thank you - Apr 23rd 2010, 03:04 PMpickslides
Shouldn't be too hard

Here's the start

Now by

we have

can you take it from here? - Apr 23rd 2010, 03:08 PMiPod
I have understood what you have done using the calculus theorem, however I don't know what to do from were you have left it, usually the ' 's would cancel out,

Sorry, could you give more clues - Apr 23rd 2010, 03:37 PMpickslides
There's only a couple of steps left to the proof, I don't want to spoil it completely!

here's a little bit more

Now factor out and in groups. - Apr 23rd 2010, 03:57 PMiPod
I may have got it I think,

but can be written as as h tends to zero

thus as h tends to zero

am I correct? - Apr 23rd 2010, 04:02 PMpickslides
(Nod)

Nice work! - Apr 23rd 2010, 04:03 PMiPod
wahay, kinda guessed that,

thank you very much :)