Is d/dxf(x) the Same as f'(x) for Finding Derivatives?

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Jarfi
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ahhh guys, is d/dxf(x)=f'(x)?

I just don't get it, my classmates are finding the deravative of f(x), i'd think that d/dx(f(x))=f'(f(x))=some annoying long equations...

but they get d/dx(f(x))=f'(x)? am I doing a silly mistake here?
 
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Jarfi said:
I just don't get it, my classmates are finding the deravative of f(x), i'd think that d/dx(f(x))=f'(f(x))=some annoying long equations...
Your classmates are right. Your mistake seems to be in thinking that d/dx is the same as f'. It's not. d/dx is an operator that works on a function; f' already is a function.

## \frac{df(x)}{dx}## and f'(x) are essentially two different notations for the same thing.
Jarfi said:
but they get d/dx(f(x))=f'(x)? am I doing a silly mistake here?
 


Mark44 said:
Your classmates are right. Your mistake seems to be in thinking that d/dx is the same as f'. It's not. d/dx is an operator that works on a function; f' already is a function.

## \frac{df(x)}{dx}## and f'(x) are essentially two different notations for the same thing.

damn I'm stupid... well thanks a LOT. It's 1 am but who needs sleep! go homework&euroshopper energy drink