- #1
forty
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I'm trying to prove that:
lim(x->a) e^f(x) = e^lim(x->a)f(x) (Assume lim(x->a)f(x) exists)
However I am having great difficulty! My only real approach I have taken is epsilon-delta proof.
if [tex]\epsilon[/tex] > 0 then there exists [tex]\delta[/tex] > 0 such that if |x - a| < [tex]\delta[/tex] then | e^f(x) - e^lim(x->a)f(x)| < [tex]\epsilon[/tex].
Assume [tex]\epsilon[/tex] > 0
Assume |x - a| < [tex]\delta[/tex]
then to show that | e^f(x) - e^lim(x->a)f(x)| < [tex]\epsilon[/tex]
Here I really have no idea...
As the limit of f(x) exits and that |x - a| < [tex]\delta[/tex] then by definition lim(x->a)f(x) = L (some number)
which gives
| e^f(x) - e^L| < [tex]\epsilon[/tex]
Here I have no idea.. Do I use logs? Taylor series?
This has started to give me quite a headache! I've done proofs like this before but with concrete numbers not functions.
Any help on this as always would be greatly appreciated!
lim(x->a) e^f(x) = e^lim(x->a)f(x) (Assume lim(x->a)f(x) exists)
However I am having great difficulty! My only real approach I have taken is epsilon-delta proof.
if [tex]\epsilon[/tex] > 0 then there exists [tex]\delta[/tex] > 0 such that if |x - a| < [tex]\delta[/tex] then | e^f(x) - e^lim(x->a)f(x)| < [tex]\epsilon[/tex].
Assume [tex]\epsilon[/tex] > 0
Assume |x - a| < [tex]\delta[/tex]
then to show that | e^f(x) - e^lim(x->a)f(x)| < [tex]\epsilon[/tex]
Here I really have no idea...
As the limit of f(x) exits and that |x - a| < [tex]\delta[/tex] then by definition lim(x->a)f(x) = L (some number)
which gives
| e^f(x) - e^L| < [tex]\epsilon[/tex]
Here I have no idea.. Do I use logs? Taylor series?
This has started to give me quite a headache! I've done proofs like this before but with concrete numbers not functions.
Any help on this as always would be greatly appreciated!