Exponential Diffrentiation (1 Viewer)

jaychouf4n

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Simplify then diffrentiate e^log x

ok so i'm not sure what they mean by simplify

i get e^log x/x by chain rule

the answer in the back is 1

Can you please explain the reasoning for me :)

Here log is ln because it is cambridge
 

Iruka

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The logarithmic and exponential functions are inverses of each other, so e^logx = x.
 

Mark576

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The exponential and natural logarithmic functions are mutually inverse, so they will cancel each other when applied together. So eln x = x, and the derivative is then obviously 1, as required.
 
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lolokay

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Forbidden. said:
Prove it.
e to the power [the power e must be put to to make it equal to x] = x

or you could say
ln x = a
e^a = x
e^ln x = e^a = x

but the definition is sufficient imo
 

lolokay

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eh? ln x = a, therefore e^a = x. is true by a definition. I was just saying that e^ln x = x is also true basically by definition, so you don't really need to prove it
 

Aerath

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Can't you do?
RTP: e^lnx = x
Let y = e^lnx
(Log both sides)
ln y = ln e^lnx
lny = lnx*lne
lny = ln x
y = x

Therefore:
e^lnx = x

Or am I totally off track? =\
 

vds700

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Aerath said:
Can't you do?
RTP: e^lnx = x
Let y = e^lnx
(Log both sides)
ln y = ln e^lnx
lny = lnx*lne
lny = ln x
y = x

Therefore:
e^lnx = x

Or am I totally off track? =\
thats the way i would do it, its fine.
 

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