SOLUTION: I'm stuck trying to prove the following inequality for positive real numbers 'n', where 'e' is a sufficiently small positive real number. Do you have a clue, technique, or referen

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Question 1065200: I'm stuck trying to prove the following inequality for positive real numbers 'n', where 'e' is a sufficiently small positive real number. Do you have a clue, technique, or reference for me to try?
(sqrt(n*n + e*e) - n) < (n - sqrt(n*n - e*e))
I came across this inequality in the study of limits.

Answer by ikleyn(52798) About Me  (Show Source):
You can put this solution on YOUR website!
.
Imagine the plot of the function y = sqrt%28x%29.


The difference sqrt%28n%5E2+%2B+e%5E2%29+-+n is the same as the difference sqrt%28n%5E2+%2B+e%5E2%29+-+sqrt%28n%5E2%29 and is the increment 
of the function y = sqrt%28x%29 at the point x = n%5E2 when you increase the argument "x" by the value of e%5E2.


The difference n+-+sqrt%28n%5E2+%2B+e%5E2%29 is the same as the difference sqrt%28n%5E2%29+-+sqrt%28n%5E2+-+e%5E2%29 and is the increment 
of the same function y = sqrt%28x%29 at the point x = n%5E2-e%5E2 when you increase the argument "x" by the value of e%5E2.


Then your statement follows the fact that the function y = sqrt%28x%29 has lower grade at the point x = n%5E2 than at the point x = n%5E2-e%5E2.


Very visual proof.