Evaluating the Limit: $\frac{e^{tan(x)}-e^x}{tan(x)-x}$

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Homework Statement


Evaluate the following limit:-
\lim_{x→0} \frac{e^{tan(x)}-e^x}{tan(x)-x}

Homework Equations


The Attempt at a Solution


Here are my attempts:-
I firstly apply L'Hospital rule, i get:-
\lim_{x→0} \frac{e^{tan(x)} \cdot sec^2(x)-e^x}{sec^2(x)}

If i directly substitute 0 here, i get the answer to be 0 but WolframAlpha says its 1. :confused:

I don't understand where am i wrong? :(
 
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Pranav-Arora said:

Homework Statement


Evaluate the following limit:-
\lim_{x→0} \frac{e^{tan(x)}-e^x}{tan(x)-x}


Homework Equations





The Attempt at a Solution


Here are my attempts:-
I firstly apply L'Hospital rule, i get:-
\lim_{x→0} \frac{e^{tan(x)} \cdot sec^2(x)-e^x}{sec^2(x)}

If i directly substitute 0 here, i get the answer to be 0 but WolframAlpha says its 1. :confused:

I don't understand where am i wrong? :(
After applying L'Hopital's Rule, you're missing a term in the denominator.
\lim_{x→0} \frac{e^{tan(x)} \cdot sec^2(x)-e^x}{sec^2(x) - 1}

This is still of the indeterminate form [0/0].
 
Mark44 said:
After applying L'Hopital's Rule, you're missing a term in the denominator.
\lim_{x→0} \frac{e^{tan(x)} \cdot sec^2(x)-e^x}{sec^2(x) - 1}

This is still of the indeterminate form [0/0].

Lol, sorry. :D

Yeah, it is still of 0/0 form but when i again apply L'Hosiptal, it is still of 0/0 form. :(

If i try to apply L'Hospital rule again and again, i am getting a 0 in denominator which will make my answer infinity, and the answer isn't that.

Is there any other method?
 
Pranav-Arora said:
Lol, sorry. :D

Yeah, it is still of 0/0 form but when i again apply L'Hosiptal, it is still of 0/0 form. :(

If i try to apply L'Hospital rule again and again, i am getting a 0 in denominator which will make my answer infinity, and the answer isn't that.

Is there any other method?

The first and second derivatives the denominator are zero. The third derivative isn't.
 
Dick said:
The first and second derivatives the denominator are zero. The third derivative isn't.

Yeah it isn't.

Sorry again. I was doing some oral calculation, so i think i made a mistake. Sorry. :)

EDIT: Thanks for all the help. I have solved the problem. :)
 
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