Integrability of sin(1/x) on [0,2]

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SUMMARY

The function f defined as f(x) = sin(x) for x ≤ 0 and f(x) = sin(1/x) for x > 0 is integrable over the interval [-2, 2]. The primary concern is the behavior of sin(1/x) as x approaches 0. The function is continuous everywhere in the interval except at the finite point x = 0, leading to the conclusion that f is integrable on [0, a] for any a > 0, particularly when considering the limit as ε approaches 0.

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Homework Statement


f is defined by: for x=<0 f(x) = sin(x). for x>0 f(x) = sin(1/x).
Is f integrable in [-2,2]?


Homework Equations





The Attempt at a Solution



I think that the answer is yes because f is continues for all x in [-2,2] except for a finite amount of points (x=0). Is that right? It just seems weird that a function as chaotic as sin(1/x) could be integrable around 0.
Thanks.
 
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It looks like you are right.

As you already remarked, the problematic point is x = 0.
Actually, the question reduces to: is sin(1/x) integrable on [0, a] (with a > 0).
So is it integrable on [[itex]\epsilon[/itex], 2] and what happens if you take [itex]\epsilon \downarrow 0[/itex]?
 

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