How to Prove the Inequality e^x > (1 +f(x)/n)^n for x in (0, infinity)?

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SUMMARY

The inequality e^x > (1 + f(x)/n)^n for x in (0, infinity) is under scrutiny, particularly when f(x) is bounded between 0 and infinity. The discussion highlights the need to analyze the series representation of e^x and the binomial expansion of (1 + f(x)/n)^n. It is established that the inequality does not hold for specific values, such as n=1 and f(1)=2, indicating potential errors in the original problem statement. The conclusion suggests that the intended inequality may have been e^f(x) instead.

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Homework Statement


If 0 <= f(x) < infinity, then I need to show that e^x > (1 +f(x)/n)^n for x in (0, infinity)


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The Attempt at a Solution


I'm pretty sure the answer lies in the comparison of the series representation for e^x and writing (1 +f(x)/n)^n out with the binomial theorem. I did so, however I still don't see it.
 
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Is this supposed to be true for all n, or the limit as approaches infinity or what? Suppose f(0)=1 then the statement is false for n=1, and x=0.
 
for all n, and x > 0 though.
 
regularngon said:
for all n, and x > 0 though.

Again take n=1, and any function f(x) such that f(1)=2, and it is false.
 
Yea it must be a typo on my teachers part. I'm going to guess he meant e^f(x).
 
Well in that case writing out the series expansions for both sides of the equation would help.
 

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