Show integrable is uniformly continuous

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The discussion centers on proving that the function F(y) = ∫[a to b] f(x,y) dx is uniformly continuous, given that f: H → R is continuous and g: [a,b] → R is integrable. The key insight is that since H = [a,b] × [c,d] is compact, the function f is uniformly continuous. This property allows for the establishment of continuity of F(y) at any point y0, leading to the conclusion that F(y) is uniformly continuous over the interval [c,d]. The proof hinges on the relationship between the uniform continuity of f and the compactness of the domain.

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H = [a,b][tex]\times[/tex][c,d] . f:H[tex]\rightarrow[/tex]R is continuous, and
g:[a,b][tex]\rightarrow[/tex]R is integrable.

Prove that
F(y) = [tex]\int[/tex]g(x)f(x,y)dx from a to b is uniformly continuous.


I initially ripped g(x) and f(x,y) apart and tried to show each was continuous. This failed.
In short, I am completely stuck. Please help me.
 
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g(x) is only given as integrable, not necessarily continuous so that couldn't work.
 
Hint: since H is compact, f is, in fact, uniformly continuous. Use that to show for all epsilon>0, there exists a delta>0 such that |f(x,y0)-f(x,y)|<delta for all y such that |y-y0|<delta (for all x). Use that to show that the integral F(y) is continuous at y0. Once you know it's continuous, you don't have to worry about the uniform part, since y is in [c,d], which is also compact.
 

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