Do Products of L^2 Functions Converge in the Integral?

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Hi i have a question about [itex]L^2[/itex] spaces and convergence.
Here it goes:
Let [itex]K\subset \mathbb{R}^2[/itex] be bounded.
Let [itex]g,h\in L^2(K)[/itex], and a sequence [itex]f_n\in L^2(K)[/itex] such that [itex]f_n[/itex] converges strongly to [itex]f\in L^2[/itex].
Is it true that [itex]\lim_{n\rightarrow \infty} \int_{K} f_n g h = \int_{K} f g h[/itex]? If it is how?
Thank you.
 
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[itex]g,h \in L^2[/itex], then [itex]gh\in L^1[/itex] by Holder inequality.

and so I do not know the integral [itex]\int_K fgh[/itex] is well-defined?
 
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zhangzujin said:
and so I do not know the integral \int_K fgh is well-defined?

I didn't get what you mean. Are you asking it as a question?
 
zhangzujin said:
[itex]g,h \in L^2[/itex], then [itex]gh\in L^1[/itex] by Holder inequality.

and so I do not know the integral [itex]\int_K fgh[/itex] is well-defined?
Yes. [itex]L^2[/itex] consists of functions whose square is integrable. The product of any two such functions is integrable but the product of three of them may not be.
([itex]L^2[/itex] is not closed under multiplication.)