Help with integration proof with epsilon-delta

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The discussion centers on proving that if a function f is continuous on the interval [a,b] and the integral of its absolute value over that interval equals zero, then f(x) must equal zero for all x in [a,b]. The user intends to use an epsilon-delta proof by contradiction, assuming the existence of a point c where f(c) is not zero. They plan to show that this leads to a contradiction by demonstrating that |f(x)| can exceed epsilon/2, thus violating the initial condition. The integration method discussed is Riemann integration.

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Ara macao
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Prove that if f is continuous on [a,b] and

[tex]\int_a^b |f(x)|\,dx = 0[/tex]

then f(x) = 0 for all x in [a,b].

so I'll have to use an epsilon delta proof by contradiction here. I'll have to assume that there exists a c such that f(c) != 0 and for all x = f(c)/2, there exists a delta such that |f(x)-f(c)|< epsilon for |x-c| < delta. and then I should make |f(x)| > epsilon /2. This would contradict the original hypothesis...

But I'm getting confused here...

Thanks!
 
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Are you using Riemann integration or Lebesgue integration?
 
Riemann integration
 

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